『経済研究』（明治学院大学）第 145 号

2012 年

Silk and Sakoku: a simulation analysis ofindustrial location in Edo period Japan
Toshihiro ATSUMI＊
Faculty of Economics, Meiji Gakuin University
GEP, University of Nottingham

Abstract
Japan closed itself to international trade from the 17th century to the mid-19th century during the Edo period, known as the Sakoku. After the closure, industries dispersed from western
coastal cities to inland areas in western and eastern Japan. This paper investigates how the Sakoku
may have aﬀected industrial locations within Japan by applying a footloose entrepreneur type geography model to an economy with agricultural raw materials in a continuous space setting. The
simulations based on this model show that agglomeration of industries such as silk fabric production in western coastal cities no longer become sustainable after the closure, and relocates to inland
places forming new cities.
JEL Classiﬁcations: F12, L67, N95, R12
Keywords: International trade, economic geography, Japan

1．Introduction
Silk fabric production in Japan ﬁrst emerged in western ports which had better access to the
Asian continent to import raw silk, because Japan at the time could not produce raw silk eﬃciently
on a commercial basis. The earliest silk fabric production sites include Hakata, Sakai and Kyoto＊

I would like to thank Rod Falvey and Daniel Bernhofen for helpful comments and suggestions. I also thankthe participants in the seminar at the University of Nottingham. I am responsible for all remaining errors.
E-mail: atsumito@eco.meijigakuin.ac.jp101

『経済研究』（明治学院大学）第 145 号

which is also known as the ﬁrst case of industrial agglomeration in Japan.
However, the Tokugawa regime that came into power in the 17th century decided on a policyof self-imposed isolation that lasted two centuries. The port closure in the late 17th century resulted
in the introduction of raw silk production in eastern Japan, where climate and mountainous land was
not suitable for crops like rice. Following the isolation, the silk fabric industry dispersed to the eastern inland regions, while Kyoto in the west also remained as a major silk fabric production site. Newly developed silk fabric manufacturing sites in the east in this era include the city of Kiryu, which is
known to have become a rival of Kyoto.
The silk fabric industry of Japan had experienced drastic changes in its environment: the ﬁrst
phase can be characterized by silk fabric production based on imported raw materials; the firstshock occurred in the late 17th century when the ports were closed (phase 2); the second shock camein the mid- 19 th century when the ports were reopened and international trade in textiles started(phase 3). The aim of this paper is to explain the phase 1 geography and the transition to phase 2.1
This is done by applying a footloose entrepreneur type geography model developed by Forslid andOttaviano (2003) to an economy with agricultural raw materials in a continuous space setting. By introducing continuous space, cities and hinterland within regions can be taken into account, which allows an analysis of economic geography at a ﬁner level.
The analysis of cities and hinterland based on the new economic geography framework wasdeveloped by Fujita and Krugman (1995), which is known as the monocentric economy model. This
paper also makes use of their idea of modelling a city as a manufacturing site in one dimensional continuous space. However, it departs from their monocentric economy model in which the economy
consists of one type of worker and a simple agricultural sector supplying agricultural goods to thecity, by introducing skilled and unskilled workers who are mobile between sectors, or mobile between the city and the hinterland, and the agricultural sector that produces raw materials in the hinterland.
The evolution of cities and the system of cities have been investigated by researchers including Fujita and Mori (1997) and Fujita et al. (1999), based on the monocentric economy model. Their
analyses demonstrate systems of cities created by exogenously increasing population. The focus of
this paper is on the impact of external shocks such as the port closure, since population was stagnant
in this era.
The main ﬁnding of this paper is that while providing feasible economic reasoning, the model
can roughly simulate the changing location of the silk fabric industry in relation to the changing economic environment: agglomeration in the west as an initial equilibrium in phase 1, dispersion of silk

1

The geographic impact of the reopening of the ports in the mid-19th century is analysed in Atsumi (2010).
102

Silk and Sakoku: a simulation analysis of industrial location in Edo period Japanfabric production to the eastern inland region in phase 2 during isolation.
This paper is organised in the following way. The next section presents the basic model andits application to the phase 1 geography. The initial equilibrium and the sustainability of the geographic structure are examined. In Section 3 the impact of the port closure is analysed. Section 4
demonstrates a possible dynamic process that leads to the formation of a new geographic structurein phase 2 during the economic isolation in the Edo period. Section 5 concludes.

2．Explaining economic geography in phase 1
The economic geography of Japan in this era is modelled as in Figure 1, which is described indetail in the next subsection.

Figure 1: The phase 1 geography

Home
west

east

hE
hW

easternhinterland

westernhinterland
food

intra-regional
A M
transport cost：eτ dmountains

food

A M

eτ d

silk fabrics
port city

P

P

port

t A，M

raw silk
foodcultivated area：

Foreign

city：
port：

2.1

P

Basic assumptions

Goods, production technology, and market structure
There are three goods in the economy; diﬀerentiated silk fabrics and two homogeneous agricultural goods - raw silk for silk fabric production and food. Production of silk fabrics requires raw
103

『経済研究』（明治学院大学）第 145 号

silk and two types of labour, skilled and unskilled. A ﬁrm producing a particular variety of silk fabrics requires a ﬁxed number (α) of skilled workers and one unit of raw silk and β unskilled workers
per unit output. The ﬁrm thus faces increasing return to scale. Its total cost for producing a given
M

⎝⎛

⎝⎛

⎝⎛

⎝⎛

amount q is thenc qM ＝αwS＋ βwU＋pR qM,
S

(1)
U

R

where w is the wage of skilled labour, w is the wage of unskilled labour and p is the price of raw
materials. It is assumed that manufacturing ﬁrms are monopolistically competitive.
On the other hand, agriculture is a constant returns sector which uses only unskilled labour
combined with land. Due to the climate diﬀerences between the east and the west, we assume thatfood production is less eﬃcient in the east. In other words, the east has a comparative advantage inraw silk while the west has a comparative advantage in food. Perfect competition is assumed for foodproduction.

Geography and transport cost
There are two domestic regions, the east and the west. Transport costs exist between themand inter-regional transport can only take place through the two ports: goods cannot be shipped directly to the other region from hinterlands or non-port cities. This assumption ﬁts into a country like
Japan where inland locations are mountainous, and so inter-regional transport took place between
port cities on the coastline.2 Inter-regional transport cost is expressed in iceberg form, t (＞1). An iceberg transport cost of t implies that t units of a good needs to be shipped in order to supply a unit of
the good to a destination. In other words, t−1 units are lost during transport. Transport costs forsilk fabrics and agricultural goods (food and raw silk) can diﬀer with iceberg transport costs for silkMA

fabrics and agricultural goods expressed as t and t , respectively.
Further, one dimensional continuous space is introduced within regions in order to distinguishbetween cities, ports and hinterlands. Cities are deﬁned as silk fabric production sites and can locate
anywhere. This implies that in addition to the inter-regional transport costs t

M A, intra-regional trans-

port costs, that is, the transport costs between the port, the city, and its hinterland are take into account. The iceberg transport cost function of silk fabrics between locations with distance d is τ (d) ＝MMeδ d (δM ＞ 0, d ＞ 0). In particular, if the length of the hinterland is hr (r=E, W) then the iceberg transport cost between the port and the frontier, or the edge of hinterland, will be e
2

δMh 3

. Similarly, the ice-

Ochiai (2007) describes the goods transported through the main ocean route between Osaka and Edo (current
Tokyo), which includes basic food (such as rice), fabrics, soy sauce, sake, and vegetable oil. See also the map in

3

Subsection 2.6.
hr is variable depending on the size of agriculture in each region.
104

Silk and Sakoku: a simulation analysis of industrial location in Edo period Japan
δAd

berg transport cost function for the agricultural goods, is τ (d)=eAA(δ ＞0, d＞0).

Labour endowment
The population of unskilled workers in the country is normalized at one and that of skilledworkers is denoted by S. This implies that the total mass of ﬁrms in the country is ﬁxed at S/α inequilibrium. It is also assumed that unskilled labour is evenly distributed between the east and thewest. 4 Therefore each region has half a unit of unskilled labour.
Introduction of land as a factor of production requires modelling owners of land or landlords.
However, following Fujita and Krugman (1995), the present analysis abstracts from modelling landlords explicitly: landlords reside on the land they own and earn land rents from the unskilled workers who are cultivating the land. However, they are immobile and do not exist beyond the frontier.5

Consumer preference
All consumers have the same preferences, which are described by a two-tier utility function.
The upper tier is
U=MμF 1−μ, 0 ＜μ＜ 1(2)which implies that the income shares of μ and 1−μ are allocated for silk fabrics (M) and food (F), respectively. The second tier dictates the consumersʼ preferences over the diﬀerentiated varieties ofsilk fabrics, which is deﬁned asnM=∫ m(i) d i
ρ1ρ

, 0< ρ <1(3)0

where M is the composite of all the diﬀerentiated silk fabric varieties, n is the mass of silk fabric varieties, m(i) is the consumption of variety i, and ρ is the substitution parameter. 0 ＜ρ＜ 1 is assumed toensure that the silk fabric varieties are imperfect substitutes. To represent the elasticity of substitution between any two varieties of silk fabrics, σ＝1/(1−ρ) (σ＞1). Consumersʼ love-of-variety is stronger the smaller σ (or the smaller ρ).
By introducing a price index of silk fabricsnG=∫ p (i)

1−σ

di

1
1−σ

(4)

0

F

such that total expenditure on silk fabrics is GM, and denoting the price of food as p , indirect utility(or the real wage, ω) can be expressed as
4

The total population of the east and the west was nearly equal before the port openings in the late 19th century. (The west was slightly larger.) The east overtook the west after the port openings.

5

In other words, a landlord exists only when the land is used. They ʻdisappearʼ when the land they own is nolonger cultivated.
105

『経済研究』（明治学院大学）第 145 号

ω j=

w
μ

j

G pF

1−μ

( j = U, S ).

(5)

Labour mobility
As in the footloose entrepreneur model by Forslid and Ottaviano (2003), skilled workers are
the only mobile factor between and within the regions. Following Krugman ( 1991 ), it is simply assumed that skilled workers move to the location that oﬀers them the highest real wages. Unskilledworkers are not mobile between the regions but are mobile within the region they reside, and canbe employed in either sector within the region, that is, they can either work in the city in the silk
fabric sector or in the hinterland in the agricultural sector producing food or raw silk.
2.2

Speciﬁc assumptions in phase 1
Eastern natural conditions are less suitable for food production. Speciﬁcally, a unit of unskilled

labour combined with a unit of land produces a unit of food in the west, while fE units of unskilled labour and land are required to produce a unit of food in the east. fE ＞ 1 means that eastern food production is less eﬃcient compared to the west.
Raw silk is not produced domestically in phase 1: Japan exports food from the western port to
the Asian continent to trade for raw silk.6 The only silk fabric production site is the western port,that is, there is only one city at the western port, where S/α silk fabric ﬁrms locate.
2.3

Firm behaviour and prices by location
M

Denoting the (mill) price of silk fabrics in the western port city as P PW , and the price of (imRM

ported) raw silk as P PW , if a ﬁrm sells quantity q PW , its proﬁt (value of sales minus variable and ﬁxed⎝⎛⎝⎛

costs) ispMPW qMPW − βw UPW ＋pRPW qMPW −αw SPW.

(6)

Then to maximize its proﬁt, the monopolistically competitive ﬁrm will set price as
1

p MPW 1−σ ＝βw UPW ＋ p RPW .

(7)

The price (index) of silk fabrics at a location of distance d from the western port in the western hinterland can be expressed as

6Japanʼs main exports in the 16th and the 17th century before the port closures were primary goods including
minerals such as silver (and later copper) and other miscellaneous goods such as sulphur, handicraft, rice,wheat and dried seafood. It can be interpreted that these are included in ʻfoodʼ.
106

Silk and Sakoku: a simulation analysis of industrial location in Edo period Japan
1−σp MPW τ M (d )GWM (d ) = nW

1
1−σ

(8a)

.

(Hereafter, a location of distance d from the port is called “location d”.) In the eastern hinterland theprice index at location d is
1−σ

2.4

1
1−σ

p MPW t Mτ M (d )G ME (d ) = nW

.

7

(8b)

Demand for goods by location

Demand for food
Demand sources of food are the western port city and foreign, in addition to the demand fromunskilled agricultural workers and landlords in hinterlands. Denoting aggregate income of the western port city as YPW, food demand from the western port city is( 1−μ ) YPW
.
F
p PW

F
=
D PW

(9)

Demand for silk fabrics
Demand sources of silk fabrics are the western port city and the farms in the hinterlands consisting of unskilled agricultural workers and landlords. Denoting farm income (the sum of unskilled
agricultural workersʼ and landlordʼs income) of location d in the west and the east as YW (d) and YE (d),respectively, total demand for a typical variety of silk fabric, including inter-regional and intra-regional transport costs, is
−σ

σ−1

M
M
D PW
) (GPWM ) μYPW
= ( pPWhE

M t M τM s()
+ ∫ p PW

s=0hw

M τM s()+ ∫ p PW−σ−σ

G EM (s)σ−1μYE (s) t M τM (s) ds，

(10)

−σ

G WM (s) μYW (s) τM (s) ds.

0

where GM
PW

M

=G W (0).

Demand for raw silk
Total input demand for raw silk from the silk fabric ﬁrms in the western port city, given theMRM

output q PW , is D PW ＝nW q PW .

7

M

The mill price is further multiplied by t to reﬂect the inter-regional transport cost from the western port tothe eastern port.
107

『経済研究』（明治学院大学）第 145 号

2.5

Spatial equilibrium in phase 1
Equilibrium requires that all goods and factor markets clear, ﬁrms achieve zero proﬁts, andthe real wage of unskilled workers in the city and the real wages in the agricultural hinterland to beequalized in the west. These conditions lead to the following results.

The agricultural sector
Farm income. Perfect competition in food production implies marginal cost pricing. Then if theFfood price in the western port city is p PW , the income of a farm at location d in the west is
YW (d )=p FPW τA(d) −1 and income of a farm at location d in the east is YE(d)=p FPW f E t A τ A (d) −1. Food andFR

raw silk are internationally traded and their prices at the western port, pPW and p PW , respectively, aregiven for Japan.

Market clearing of food. Food supply to the western port city from the western and eastern hinterlands, except for their own consumption in the farms, should be equal to its total demand from theFwestern port city and its exports to foreign (E f ):hw

∫ μ τ A(s)

hE

−1
μ
F
ds＋∫ f t A τ A(s) ds = D PW
＋E fF

−1

s=0

(11)

s=0

Unskilled wage in the western port city
Unskilled workers are mobile within the region they reside. In addition, in the west they aremobile between the silk fabric sector in the western port city and the agricultural sector in the western hinterland. The real wage of unskilled workers in the western port city is
U
ω PW
=

U
w PW

μ

(G ) ( p )
M
PW

F
PW

1−μ

,

(12)

and the real wage of agricultural workers in the western frontier, where the land rent is zero, isFτ A ( hW )p PW

ω (h W )=UWμG (hW)
M
W

{p

μ

−1
−1 ( 1−μ)F
PW

τ A ( hW )

}

=

F
p PW

G WM (hW) τ A (hW)

．

(13)

Intra-regional and inter-sectoral mobility of unskilled workers imply that these are to be equalized inequilibrium. Therefore,
μ

W

U
PW

=p

F
PW

M
GPW

G WM (hW) τ A (hW)

．

(14)

108

Silk and Sakoku: a simulation analysis of industrial location in Edo period Japan

Unskilled labour market clearing
Full employment of unskilled workers require that the supply of unskilled workers for silk
fabric production meets the demand from the ﬁrms in the western port city, that is,1
M，−hW = nW β q PW
2

(15)

where full employment of skilled workers implies nW ＝ S/α. The east does not have silk fabric production, so all eastern unskilled workers are employed in food production. Therefore hE＝1/2.

Skilled wages
In the silk fabrics sector, assuming free entry and exit, equilibrium skilled wage corresponding
to their full employment is determined by a bidding process for skilled workers, which continues until no ﬁrm can earn a positive proﬁt at the equilibrium prices. This implies that in equilibrium a ﬁrmʼssize is such that the operating proﬁt exactly matches the ﬁxed cost which is the wage paid for theskilled workers. That is,
S = p M q M − ( βw U ＋ p R ) q M .
αw PW
PW
PW
PW
PW
PW

Substituting for p
S
w PW
=

M
PW

using (7), the equilibrium skilled wage is( βw ＋p ) q
U
PW

R
PW

α (σ−1 )

(16)

M
PW

,

(17)
M

M

where the silk fabric market clearing requires q PW ＝D PW .

Balance of trade
The value of food export and raw silk import should be balanced:
P EPW E Ff ＝p RPW D RPW .
2.6

(18)

Solution of the phase 1 modelParameter settings
A common set of parameters is used throughout the analysis to solve the model numerically.
M

A

Their values are μ＝0.25, σ＝6.6, β＝0.03, t ＝1.5, and t ＝1.25.8 In order to extend the analysis to acontinuous space setting as in Figure 2, the additional parameters to be set are the δʼs for the intraregional transport cost functions, τM A(d). Since each region has half a unit of unskilled labour, themaximum length of the hinterlands are also 0.5 (when all unskilled labour is employed in the agriculA

tural sector). It is assumed that δ ＝0.45 so that the iceberg transport cost of agricultural goods be-

8

See Atsumi (2010) for the background information of these parameter values and further historical evidence.
The values of S and α do not aﬀect geography. Therefore, S＝1 and α＝1 are used for the numerical solutions.
109『経済研究』（明治学院大学）第 145 号
Figure 2: Inter-regional and intra-regional transport in Japan1

intra-regional transport（West）
M

2
3

A

τ（d），τ（d）

2
3

Kyoto/Osaka
25
33 32

37

28

27
30

34 35
36

31

11
24
26 22
30
29

23

12
20

19

21 18

10

2
14 6

15
17

2

9

4

13 7
16

intra-regional transport（East）

5

τM（d），τA（d）

Kiryu

8

Edo（Tokyo）

The Kansai region
and its hinterlandinter-regional transport（Osaka-Edo route）

West

The Kato region
and its hinterland

Eastt M，t A

Note: The Hokkaido island (region 1 in the map) was not well integrated to the mainland economy until the20th century. The southern part of regions 2 is considered as the peripheral areas (or the frontier) of easternJapan.

Figure 3: Intra-regional transport cost function
MAτ（d），τ（d）
1.5

1.4

τM（d）＝e0.8＊d

1.3

1.2
τA（d）＝e0.45＊d

1.1

1

0

0.1

0.2
0.3
distance from the port

110

0.4

0.5

d

Silk and Sakoku: a simulation analysis of industrial location in Edo period Japan

tween the port and the frontier of the hinterland within each region is at most τ (0.5)＝e0.45＊0.5㲓1.25.
A

This assumption is used because according to a survey by Dainihon Sanshi Kai (The Silk Industry
Association of Japan) (1935), the delivered price of raw silk from the city of Maebashi, located in the
North end of the Kanto region in eastern Japan, to Yokohama port was on average around 20% higher than the price at the origin during the period 1859 to 1867. As for the intra-regional transport costof manufactured goods, it is assumed that the transport cost (loss) is twice compared to that of the
agricultural goods. Therefore, δ ＝0.8 so that τ (0.5) ＝ e0.8＊0.5 㲓 1.5. The intra-regional transport costMMfunctions for agricultural and manufactured goods are graphed in Figure 3.

Numerical solution
F

The model is solved choosing food at the western port as the numeraire, that is p PW ＝1. Solutions of the main endogenous variables for diﬀerent levels of the eastern food productivity (fE) andR

the port price of imported raw silk ( pPW ) are shown in Table 1. It can be seen that higher productivity of food in the east and/or lower relative price of raw silk leads to higher wages and real wages. In
addition, lower relative price of raw silk leads to a smaller western hinterland. This is because thesilk fabric industry in the western port city expands and employs more unskilled workers from thewestern hinterland.

Table 1: Solution of the phase 1 model for diﬀerent levels of eastern food productivity（f E ）and imported raw silkR
price（p PW
）
fE＝ 1

fE＝ 2

fE＝ 3

p RPW

p RPW

p RPW

p RPW

p RPW

p RPW

p RPW

p RPW

p RPW

＝2

＝1

＝0.25

＝2

＝1

＝ 0 .2 5＝2＝1＝ 0 .2 5w SPW

0.03173

0.03174

0.031770.02468

0.02469

0.02471

0.02233

0.02234

0.02236w UPW

0.85600.85670.86050.85590.85640.85940.85580.085630.08590

2.387

1.209

0.325

2.387

1.209

0.325

2.387

1.209

0.325

hW

0.497

0.495

0.481

0.498

0.496

0.485

0.498

0.496

0.486

S

0.02550.03020.04210.01960.02350.03270.01800.02130.0296

P MPW
M

＝G PW

ωPW

Note: fE ＞ 1 implies that the eastern food production is less eﬃcient than to that of the west. See Subsection 2.2.

Since this is a continuous space geography model, it is useful to express the equilibrium pricesof diﬀerent locations in the following “price schedule” form; Figures 4a and 4b show the prices of food111

『経済研究』（明治学院大学）第 145 号

and silk fabrics, respectively, of all domestic locations for the fE＝3 case. Figure 4a indicates that thewestern port city, where food from the eastern and western hinterlands were shipped to, has thehighest food price. The gap between the western port price and the eastern price reﬂects both thetransport cost and the productivity diﬀerence. Figure 4b indicates that, since silk fabrics were only
produced in the western port city, its price in the city is lowest and prices for the consumers in theeastern hinterland were high because of the inter-regional transport cost.

Figure 4a: Equilibrium price schedules of food in phase 1 with f E = 3 and p WR = 1

west（producers）
1

east（producers）

earned price by western farmers p FPW＝1A−1p FPW（eτ d）
land rent
transport cost&productivity diﬀerence

0.8
agricultural wage

0.6

earned price by eastern farmers

0.4−1
p FPW（ fEt A）

0.2
0.4
0.3
0.2
distance from port

consumers
d
0.1
0
port
city

A

−1
p FPW（ fEt Aeτ d）

land rent0
port

agricultural wage

0.1
0.2
0.3
0.4
distance from portdFigure 4b: Equilibrium price schedules of silk fabrics in phase 1 with f E = 3 and p RPW = 1
1
0.9

west
（consumers）

east（consumers）

0.8
0.7
0.6

M

M
pM
PW t
τ d
pM
PW e

pM
PW

0.5
0.4
0.3

2.7

M τ d
pM
PW t eMtransport costconsumers/producers
0.4
0.3
0.2
distance from port

0.1

0
port

0
port
city

0.1

0.2
0.3
0.4
ditance from portdSustainability of the western port city
The market potential functions are deﬁned and are evaluated for all values of d ＜― hr (r＝E, W )using the results from the numerical solution in Table 1. They indicate under what conditions thegeography with a single western port city can be sustainable.
The geographic structure with a single port city in the west can be considered sustainable112Silk and Sakoku: a simulation analysis of industrial location in Edo period Japan

when no location has a market potential exceeding unity, because this indicates that no location ismore proﬁtable than the city, and that no ﬁrm has an incentive to leave the city.

The market potential function of the west
Given the equilibrium prices, ﬁrms calculate hypothetical proﬁts (the operating proﬁt minus ﬁxed
costs of locations other than the city), that is,~~~ (d ) = ~πp WM (d ) D WM (d )− βw WU (d )＋p WR (d ) D WM (d ),
W

(19)

R

where pW (d) is the price of raw silk at location d in the west,

μ

−1

U
w WU (d ) = w PW~
p WM (d ) =

F
PW

μ

A

(G ) ( p )
M
PW

σ
σ−1

(1−μ)

p τ (d )G (d )
M
W

F
PW

(20a)

，

1−μ

βw WU (d )＋p WR (d ) ，

(20b)

and

σ−1

YPW ( G MPW )×

τ M (d )hE＋ ∫ YE (s) G ME (s)

1−σ

hW

＋ ∫ YW (s) G W (s )

σ−1

M

σ−1

s=0

τ M (d ) t M τ M (s )

τ M ( d−s )

1−σ

ds

s=0

1−σ

ds

⎩―⎨―⎧

⎩―⎨―⎧

−σ
~
D WM (d ) =μ ~p WM (d )(20c)．

(20a) is the unskilled workersʼ wage at location d in the west. This is reﬂected in (20b) which meansthat the hypothetical mill price at that location will be based on the unskilled wage and the price ofraw silk at that location. The hypothetical demand shown in (20c) is therefore based on this hypothetical mill price.
〜S
The hypothetical ﬁxed cost of operating at location d in the west is αw
E (d), whereμS~WS (d ) = w PW
w

−1

(1−μ)

F
τA (d )p PW

G (d )MWμ(G ) ( p )
M
PW

F
PW

(21)

1−μ

is the hypothetical skilled wage compensated for the changes in the living cost of relocating to location d. The market potential function in the west is deﬁned as~ (d )πΩW (d ) = ~WS．
αw W (d )

(22)

113

『経済研究』（明治学院大学）第 145 号

The market potential function of the east
The hypothetical operating proﬁt at location d in the east is~~~ (d ) = ~πp EM (d ) D EM (d )− βw EU (d )＋p ER (d ) D EM (d ) ，E(23)

where p RE (d) is the price of raw silk at location d in the east,σ~p WM (d ) =βw EU (d )＋p ER (d ) ，
σ−1

(24a)
μ

w (d ) = p
U
W

A

1−μ

τA (hE )G EM (hE )τA (d )

−1

fE t τ (hE )AF
PWG EM (d )

，

(24b)

and

σ−1

YPW ( G MPW )τ M (d ) t M

hW( ) G W (s )× ＋ ∫ YW s

σ−1

M

1−σ

τ M (d ) t M τ M (s )

1−σ

s=0

hE

＋ ∫ YE (s) G ME (s)σ−1τ M ( d−s )

1−σ

ds

s=0

ds

⎧――⎨――⎩⎩――⎨――⎧−σ~
D EM (d ) =μ ~p EM (d )

(24c)
．

〜S
The hypothetical ﬁxed cost of operating at location d in the east is αw
E (d), whereμ~ES (d ) = w PWSw

G (d )
M
E

−1

p

F
PW

μ

A

(G ) ( p )
M
PW

(1−μ)

t τ (d )
A

F
PW

(25)

1−μ

is the hypothetical skilled wage compensated for the changes in the living cost of relocating to location d. The market potential function of location d in the east is deﬁned as~ (d )πΩE (d ) = ~E S．
αw E (d )(26)＜
The city is sustainable if ΩE (d ) ＜― 1 and ΩW (d ) ― 1 for all d, because otherwise ﬁrms decide they canleave the western port city and proﬁtably move to other locations.
The calculated market potentials of all locations for diﬀerent levels of the eastern agricultural productivity ( fE) are shown in Figure 5a for the east and in Figure 5b for the west. Figures 6a andR

6b show the market potentials for diﬀerent levels of the port price of imported raw silk (pPW ), ﬁxing
the level of fE. They indicate that the geography with a single port city in the west is sustainable inphase 1 if agricultural (food) productivity of the east is suﬃciently lower than the west and/or if raw
silk is suﬃciently expensive relative to food. Low food productivity in the east is consistent with thehistorical understanding that the natural condition of eastern Japan (particularly in mountainous
114

Silk and Sakoku: a simulation analysis of industrial location in Edo period Japanplaces) was not suitable for crops like rice and that the farmers there were poor before the introduction of sericulture.
The result can be interpreted as follows. The western port is the best location in terms of raw
silk cost. However, it is not necessarily the best location for supplying silk fabrics for (domestic) consumers because in this era Japanese silk fabrics were not exported. If the eastern agricultural technology is high, which implies higher agricultural income, ﬁrms in the western port may ﬁnd proﬁtable locations in the east, because it is advantageous to supply to the eastern market (as in the fE＝1
or the fE＝2 cases in Figure 5a). The eastern regions are, however, understood to have been inferiorin agricultural productivity due to natural conditions. Therefore, the east was not as attractive as thewestern port which had the best access to imported raw materials; under low food production technology in the east and/or high raw silk price, it is likely that the economic geography with a single
western port city was sustainable in phase 1 as in the fE＝3 case shown in Figures 5a and 5b.

Figure 5a: Market potential of the east in phase 1（p RPW ＝1）
Ω（d）
E

fE＝1

1.6
1.4
1.2
port

fE＝2
0.1

0.2

0.3

d

0.4

0.8
fE＝3
0.6
western port city is sustainable

0.4

Figure 5b: Market potential of the west in phase 1（p RPW ＝1）
ΩW（d）
port city

0.1

0.2

0.9

0.6

0.4
fE＝3

0.8
0.7

0.3

fE＝1
fE＝2

0.5
0.4

115

d

『経済研究』（明治学院大学）第 145 号
Figure 6a: Market potential of the east in phase 1（f E ＝3）
ΩE（d）

p RPW＝0.25

1.1
port

0.1

0.2

0.3

d

0.4

0.9
0.8
p RPW＝1

0.7
0.6
0.5

western port city is sustainable

0.4

Figure 6b: Market potential of the west in phase 1（f E ＝3）
ΩW（d）
port city

0.1

0.2

0.3

d

0.4

0.9
p RPW＝0.25

0.8
p RPW＝1

0.7
0.6
0.5

3．The impact of the port closures in the late 17th century on the phase 1 geography
The port closures in the late 17th century implied a total loss of raw silk supply. Following theclosure, domestic production of raw silk started in the east, which had a comparative advantage inraw silk production due to the diﬀerences in the natural conditions. This section considers the impactof the port closure and the resulting domestic raw material production on the phase 1 geography
with a single western port city. It investigates whether the single city in the western port is still sustainable under the change in the environment (Figure 7).

116

Silk and Sakoku: a simulation analysis of industrial location in Edo period Japan
Figure 7: The phase 1 geography after the port closure (late 17c)

west

east

hE
hW

easternhinterland

westernhinterland
food

τA Md

e

mountains

raw silk

A M

eτ d

silk fabrics
port city

P

port

P
t A，M

no international tradecultivated area：
city：
port：

3.1

P

Modiﬁcations of the model to account for port closure and domestic raw material production

Geography and transport cost
There is no international trade due to the port closure. The same domestic transport cost assumptions are maintained.

Goods, production technology, and market structure (introduction of raw silk production)
It is assumed that food productivity in eastern Japan is so low that the eastern agricultural
sector specializes in raw silk production after the port closure.9 The production technology of raw
silk is that a unit of unskilled labour combined with a unit of land produces a unit of raw silk. Perfectcompetition prevails for raw silk production as well as for food in the west.10
3.2

Sustainability analysis of the phase 1 geography with port closure

Numerical solution
The model is ﬁrst solved numerically, assuming the same exogenous parameters used in the
9

A

A τ d

sumed to be high enough so that this holds.
10

R

/

Formal description of the model is available from the author upon request.
117

A

τ d

The necessary condition for eastern Japan to specialize in raw silk is 1/fE t e ＜pPE e

RAor 1 ＜ p PE t fE . fE is as-『経済研究』（明治学院大学）第 145 号

previous section, to obtain the equilibrium values of the endogenous variables (Table 2 ). They willthen be used in evaluating the market potential functions.

Table 2: Solution of the phase 1 geography with port closure
w SPW

0.222

U
PW

0.858

w

p RPE
P

M
PW

0.257
M
PW

(＝G )

0.409

hW

0.489

S

0.0277

ωPW

F

Note: Food at the western port city is chosen as the numeraire (p PW ＝1).

The equilibrium price schedules of phase 1 with port closure based on the results in Table 2
are shown in Figures 8a, 8b and 8c. Figure 8a is the food price schedule. Since food is now only produced in the west, prices in the east are generally higher than in the west because of the transport
costs. Figure 8b is the price schedule of raw silk. After the introduction of raw silk production in theeast, its price is lowest in the eastern frontier. Silk fabric producers in the western port city bear thetransport cost to purchase raw silk from the east. Figure 8c is the price schedule of silk fabrics. Silkfabric production is agglomerated in the western port city, where its price is lowest. Silk fabric prices are generally higher in the east because of the inter-regional transport cost. It can be foreseenfrom these results that the east is now potentially an attractive place for silk fabric production, given
the low raw silk cost and the high current prices of silk fabrics, although food is expensive in theeast.

Figure 8a: Equilibrium price schedules of food with port closure

west（producers）

east（consumers）

1.6

A

p FPW t Aeτ d

1.4
1.2
1

p FPW t A
earned price by western farmers
F
PW

τAd −1p （e ）

transport cost

p FPW＝1

land rent

0.8
0.6

agricultural wage
consumers
0.4
0.3
0.2
distance from port

0.1

0
port

0
port
city

118

0.1

0.2
0.3
0.4
distance from portdSilk and Sakoku: a simulation analysis of industrial location in Edo period Japan
Figure 8b: Equilibrium price schedules of raw silk with port closure

west
0.4

east
（producers）
p RPE traw silk cost＊

0.3

transport costearned price by eastern farmers
p RPE
A
−1
p RPE（t Aeτ d）
land rent

A

0.2
0.1

agricultural wage

silk fabricproducers

d
0.4
0.3
0.2
distance from port

0.1

0
port

0
port
city

0.1

0.2
0.3
0.4
distance from port

Figure 8c: Equilibrium price schedules of silk fabrics with port closure
0.9

west
（consumers）

east（consumers）

0.8

M

M τ d
pM
PW t e

0.7
0.6

p

M

τ d
pM
PW e

0.5

pM
PW

0.4

M M
PW

t

transport costconsumers/producers
0.4
0.3
0.2
distance from port

0.1

0
port

0
port
city

0.1

0.2
0.3
0.4
distance from portdMarket potentials of the phase 1 geography with port closure
The market potentials of the phase 1 geography with port closure are shown in Figure 9a forthe east and in Figure 9b for the west.11 Figure 9a clearly indicates that every eastern location ismore proﬁtable than the western port city since the market potentials exceed unity. Therefore, withport closure, the phase 1 geography becomes unsustainable. This is because the advantage of the low
raw silk price in the eastern hinterland outweighs the disadvantage of the inferior market access tothe existing western port city and the western hinterland from the east. In particular, ﬁrms calculatethat the inland location d＝0.45 in the east, indicated in Figure 9a, exhibits the highest market potential. It is likely then that the ﬁrms leave the western port city and a new manufacturing city emerges in the eastern inland sericulture region.

11

The market potential functions are available from the author upon request.
119

『経済研究』（明治学院大学）第 145 号
Figure: 9a: The eastern market potential of the phase 1 geography
with port closure
highest market potential（d＝0.45）
Ω（d）
E
35
30
25
20
15
10
5
port 0

d

0.1
0.2
0.3
0.4
hinterland（distance from the port）

Figure: 9b: The western market potential of the phase 1 geography
with port closureΩW（d）
port cityhinterland（distance from the port）
0.1

0.2

0.3

0.4

d

0.9
0.8
0.7
0.6

4．A Possible dynamic process of the transition from the phase 1 to the phase 2 geography
The market potentials of the phase 1 geography with port closures shown in Figures 9a and9b indicated that location d＝0.45 in the east is potentially most proﬁtable from the viewpoint of silk
fabric ﬁrms that are agglomerated in the western port city. It is likely that the proﬁt maximizing
ﬁrms with the skilled workers who are mobile between regions relocate to this eastern inland location to start production. This section considers a possible transition process from the phase 1 geography to the formation of a new geographic structure in phase 2, the economic isolation period of Japan.

120

Silk and Sakoku: a simulation analysis of industrial location in Edo period Japan

4.1

The migration process
To take into account the changes in the market potentials over time, the market potential ofregion R∈｛E, W ｝at time t from the viewpoint of silk fabric ﬁrms in region Z∈｛E, W｝ is denoted as
ΩZR t (d). ΩWE 0 (d) and ΩWW, 0 (d ) correspond to Figures 9a and 9b, respectively.
Skilled workers are mobile both inter-regionally and intra-regionally. On the other hand, unskilled workers are only mobile within the region they reside. In the hinterlands, they are food farmers in the west or raw silk farmers in the east. But if there is a city in the region, they can move tothe city to be employed by the silk fabric ﬁrms. In order to account for inter-regional and intra-regional migration of the ﬁrms and skilled workers, a sequential migration process through which theﬁrms with their skilled workers migrate away from the western port city to the (new) eastern city is
introduced:
・
λ ＝ cλ (πCE−π)，(27)

where c is a positive constant denoting the adjustment speed, πCE is the proﬁt at the eastern city,π ＝λπCE + (1−λ) πCW is the average proﬁt. This simply means that the rate of change in the reand −gional share of ﬁrms and skilled workers is proportionate to the diﬀerence in the proﬁts.12
Since there are no ﬁrms in the east initially, it is assumed that a fraction of ﬁrms and theirskilled workers migrate from the western port city to location d＝0.45 in the east which is the most
proﬁtable location according to the market potential of the east at t＝0.13 At t ＝ 1 after the ﬁrst waveof the inter-regional migration, production is newly set up at location d＝0.45 in the east, to which theeastern unskilled workers respond: some will be employed by the new silk fabric ﬁrms; those who
remain in the agricultural sector can now ship their raw silk to the new (small) city to supply the
new silk fabric ﬁrms, resulting in changes in the prices. Given the price changes, silk fabric ﬁrms,
both in the east and in the west, re-evaluate their market potential functions. They will now have revised market potential functions, ΩEE, 1 (d ) and ΩWW, 1 (d), respectively. According to the revised market
potential functions, it is assumed that the ﬁrms with their skilled workers migrate intra-regionally, if
there is a more proﬁtable location within each region. That is, in the east, silk fabric ﬁrms and theirskilled workers (or the city) moves to location d ＊ if it satisﬁes ΩEE, 1 (d ＊ )＝maxΩEE, 1 (d) ＞ΩEE, 1 (0.45). The
same also occurs in the west if ΩWW, 1 (d ＊ )＝maxΩWW, 1 (d) ＞ΩWW, 1 (0). Unskilled workers respond again bychanging the direction of their shipment of agricultural goods, if the city location changes.
Given the (new) location of the two cities and the proﬁts of silk fabric ﬁrms in these cities, the12

One reason for introducing a gradual migration process is because ʻall at onceʼ migration to form a new single
city does not result in a sustainable geography. The other reason is that there is a range of locations within
which a sustainable two city geography exists.

13

See Figures 9a and 9b.
121

『経済研究』（明治学院大学）第 145 号

next wave of inter-regional migration of ﬁrms and skilled workers occurs according to the inter-regional migration equation. The economy then proceeds to t＝2 for the next intra-regional adjustment
and migration. In this way, inter-regional and intra-regional migration occur sequentially until there
is no further incentive for any migration.
4.2

A two city model
In addition to the migration process speciﬁed in the previous subsection, a model with two cit-ies is necessary, in order to simulate the transition from the phase 1 to the phase 2 geography. A
two city geography as in Figure 10 is modelled, allowing for a city in each region which can exist in
locations other than the port. One complexity that arises from allowing for a non-port city is the direction of the agricultural goods shipment: as indicated in Figure 10, there exists a border that divides farms shipping products to the city or to the port.14 Given the prices in the port and the city,
farms can now choose where to send their products depending on their location.

Figure 10: A model of two cities

west

east

hE
τA Md

hW

e
westernhinterland
food

A M

eτ d

easternhinterland
mountainscity

raw silk

borderraw silk
shipped tothe portsilk fabrics
port
city

raw silk
shipped tothe inland city

P

P

port

t A，M
no international tradecultivated area：
city：
port：

P

Solution
During the course of migration, the model is solved for a given level of λ to derive the silk

14

The example in Figure 10 shows the case of a border existing in the east. It can also occur in the west, if thewestern city is not located at the port.
122

Silk and Sakoku: a simulation analysis of industrial location in Edo period Japanfabric ﬁrmsʼ proﬁts in the two cities. Solving the model requires the market clearing of the goods
and factors, the real wage equalization of unskilled workers within each region, and the real wageequalization of skilled workers in the two cities, together with the border condition described below
to be satisﬁed in both regions.15

The borders and the agricultural incomes
The farm at the border location d＝bE in the east should be indiﬀerent between shipping raw
silk to the port and to the eastern city in equilibrium, that is,
−1

R
R
pPE
τA ( bE ) ＝ p CE
τA ( dCE−bE )

−1

，

(28a)

R

where p CE is the price of raw silk at the eastern city. Similarly, the farm at the border location d＝bW
in the west should be indiﬀerent between shipping food to the port and to the western city in equilibrium, that is,
−1

F
R
pPW
τA ( bW) ＝ p CW
τA ( dCW−bW )

−1

.

(28b)

⎩―⎨―⎧

The eastern farm income at location d is

YE ( d )＝

−1

R
p PE
τA ( d )＜ ＜，0 d bE

，

(29a)

−1

R
p CE
τA ( dCE−d )，bE ＜ d ＜hE⎩―⎨―⎧

and the western farm income at location d is

YW ( d )＝F
p PW
τA ( d )−1＜ ＜，0 d bWF
p CW
τA ( dCW−d )

4.3

，

(29b)

−1

，bW ＜ d ＜hW

The formation of a sustainable geography in phase 2
The migration process described in subsection 4.1 is implemented, using the model of two cit-ies and the market potential functions.16 It is assumed that a fraction of the ﬁrms and skilled workers
move to the east initially.17 When production starts in the east, the prices change due to the responses by eastern unskilled workers. The price schedules at t＝0 and t＝1 for raw silk and silk fabrics areshown in Figures 11a and 11b. Figure 11a shows that the raw silk price rises (due to the congestionin the east that drives up local unskilled wages) but also that the direction of raw silk shipmentchanges: the raw silk farmers close to the new city ship to the new city instead of the port. There15

Formal description of the model is available from the author upon request.

16

The market potential functions are available from the author upon request.

17

The analysis is implemented assuming that initially 1% relocates to the east.
123

『経済研究』（明治学院大学）第 145 号

fore, as can been seen in the t＝1 price schedule, there will be a (small) peak of the raw silk price atthe new city. Figure 11b shows that the silk fabric prices are reduced in the east (because there is
now local production) and that there is a local minimum point at the new city.

Figure 11a: Price schedule of raw silk in the east at t = 1 before theintra-regional migration of ﬁrms
eastern price of raw silk at t＝1
0.26
0.25

p RPE

0.24
0.23

new city
at d＝0.45

before migration, t＝0
A−1
p RPE（eτ d）

0.22
0.21

ship to port
port

0.1

0.2

0.3

0.4

d

0.5

bordership to city

Figure 11b: Price schedule of silk fabrics in the east at t = 1
before the intra-regional migration of ﬁrms
GM
（d）
E

0.9
before migration，
t＝0
0.8
0.7
0.6
0.5

eastern silk fabric price at t＝1
new city
at d＝0.45

0.4
port

0.1

0.2

0.3

0.4

0.5

d

Given these price changes, silk fabric ﬁrms in the east and the west now have revised market potential functions of their regions, ΩEE, 1 (d ) and ΩWW, 1 (d) , which are shown in Figures 12a andFigure 12b, respectively. Figure 12a indicates that in the east, location d＝0.38 is more proﬁtable than
the initial location d＝0.45 that they migrated to. Therefore, given the change in the market potential,
the eastern city moves to d＝0.38, which is the intra-regional migration of ﬁrms and skilled workers.
This overshooting of city location occurs because as seen in Figure 11a, raw silk price is lower to theʻleftʼ of the initial city at location d＝0.45, and because as seen in Figure 11b, silk fabric prices are124

Silk and Sakoku: a simulation analysis of industrial location in Edo period Japanhigher to the ʻleftʼ of the city.
On the other hand, the western port city moves inland after the ﬁrst wave of migration. Sincea fraction of the ﬁrms and the skilled workers move out of the western port city, unskilled workers
who were employed by them leave the city as well. This implies an expansion of the western agricultural sector. From a geographic point of view, it means an expansion of the (cultivated) western
hinterland. The geographic expansion of the western market makes inland locations more proﬁtablein terms of market access to the hinterland. This is the reason why the western city moves slightly
inland.

Figure 12a: Revised market potential and intra-regional migration at

t = 1 in the east
most proﬁtable in the east
ΩEE，（d）
1
city
d＝0.4587
6city location d＝0.38
after intra-regional migration at t＝1

5
4

port

0.1

0.2

0.3

d

0.4

Figure 12b: Revised market potential and intra-regional migration at

t = 1 in the west
most proﬁtable in the west

port
city

ΩW
W，1（d）

0.9
d＝0.160.8
0.7

city location
after intra-regional migration at t＝1
0.1

0.2

125

0.3

0.4

d

『経済研究』（明治学院大学）第 145 号

After some more rounds of migration, at t = 7, the market potentials in the east and the west
start showing cusps, suggesting a convergence of city locations as in Figures 13a and 13b, respectively. (Migration continues because the east is still proﬁtable.) Then after thirty rounds the situation
shown in Figures 14a and 14b is reached, which indicates a stable two city system: the eastern city
locates at d = 0.35 and the western city at d = 0.11. The key result is that the new city in the east isfound to locate in an inland area.18

Figure 13a: The eastern market potential at t = 7city
ΩEE，7（d）
1.4
1.3
1.2
1.1

0.1

0.2

0.3

0.4

d

Figure 13b: The western market potential at t = 7
ΩWW，7（d）

city

0.9

0.8

0.7

0.6

0.1

18

0.2

0.3

0.4

d

Further details of the migration process in phase 2 are available from the author upon request.
126

Silk and Sakoku: a simulation analysis of industrial location in Edo period Japan
Figure 14a: The eastern market potential in stable equilibrium at t = 30
ΩEE，30（d）＝ΩW
E，30（d）

city

0.1

0.2

0.3

0.4

d

0.95
0.9
0.85
0.8

Figure 14b: The western market potential in stable equilibrium at t = 30
ΩEW，30（d）＝ΩW
W，30（d）

city

0.1

0.2

0.3

0.4

d

0.9
0.8
0.7
0.6

The equilibrium price schedules of phase 2 in the two city geography after migration is completed are shown in Figures 15a and 15b. Figure 15a shows the price indices of silk fabrics. Now thatsilk fabric is also produced in the east, prices in the east are greatly reduced, particularly in places
close to the new city. Figure 15b is the price schedule of the raw silk price. Raw silk prices have risen after the emergence of the new city in the east. This is due to the congestion in the east: production in the east involves hiring local unskilled workers by the silk fabric ﬁrms in the city. Competition for local unskilled workers, therefore, raises raw silk prices. This congestion is also the reason
why not all ﬁrms move to the east from the west, despite the disadvantage of higher raw silk procurement cost in the west.

127

『経済研究』（明治学院大学）第 145 号
Figure 15a: Equilibrium price schedules of silk fabrics after migration in phase 2

west（consumers）

0.9

east
（consumers）

0.8
0.7
0.6

before migration
GM
CW

0.5
0.4

before migration
0.4

0.3

GM
CE

consumers/producers
0.2

0.1
city

0
port

0

distance from port

d
0.3
0.4
city
consumers/
distance from port
producers

0.1

0.2

Figure 15b: Equilibrium price schedules of raw silk after migration in phase 2

west

east
（producers）

0.4
raw silk cost
A
＊

0.35

pRPE t Aeτ dtransport
costearned price by eastern farmers
pRPE
raw silk
silk fabriccost R τAd −1
pPE（e ）
producers before migration
＊

0.3
0.25
0.4

0.3

0.2

＊

0.1
city

0
port

0

0.1

0.2

0.3

city
distance from port

distance from portd0.4
silk fabricproducers

The sustainable geography after the west-east migration in phase 2 can be summarized as in
Figure 16: 20% of silk fabric ﬁrms with skilled workers have now moved to the eastern inland location. This explains the emergence of such cities as Kiryu, which grew rapidly in the 18th century after the port closures in an area which previously suﬀered from poor natural conditions for crop farming. The western city, now locating slightly inland, may correspond to the city of Kyoto which still
remained as the silk fabric production centre during the economic isolation.

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Silk and Sakoku: a simulation analysis of industrial location in Edo period Japan
Figure 16: Sustainable geography in phase 2 after migration

west

east

hE
hW

easternhinterland
citywesternhinterland
food

A M

eτ d

mountainssilk fabrics
20％ of ﬁrms

raw silk

A M

eτ d

silk fabrics
80％ of ﬁrms
city
port

P

P

port

t A，M
no international tradecultivated area：
city：
port：

P

5．Conclusion
The silk industry of Japan had shown several diﬀerent geographic patterns: silk fabric production ﬁrst evolved in the western port cities, but during the economic isolation period from the late
17th to the mid-19th century, commercial domestic raw silk production started in eastern Japan andsilk fabric production dispersed toward the east, creating new cities in the eastern inland areas. This
paper examined the relation between the changing geography of the silk fabric industry and the external shock, the port closures, or the Sakoku. Incorporating continuous space within each region allowed the modelling of economic geography at a ﬁner level, distinguishing ports, cities and hinterlands.
The initial geography that the silk fabric industry is agglomerated in the western port city
can be supported as a stable equilibrium if the eastern agricultural productivity is low and/or (imported) raw silk is suﬃciently expensive relative to food, which are consistent with historical observations (phase 1).
The impact of the port closure that resulted in the introduction of raw silk production in theeast was that the east, in particular the eastern inland location, becomes more proﬁtable than thewestern port city, because of the low raw silk cost. This paper developed and applied a migration
process (diﬀerent to existing studies that focus on population increase) to ﬁnd that a small new city129

『経済研究』（明治学院大学）第 145 号

will emerge in the eastern hinterland during the economic isolation era, while the west still remaining as the main production site. This may explain the coexistence of rival cities such as Kiryu in theeast and Kyoto in the west during the isolation era (phase 2).

References
Atsumi, Toshihiro (2010) “Silk, regional rivalry and the impact of the port openings in nineteenth century Japan”, Journal of the Japanese and International Economies, Vol. 24, pp. 519‑539.
Dainihon Sanshi Kai (The Silk Industry Association of Japan) (1935) Nihon Sanshigyoshi, dai 1 kan, Kiito boekishi (Thehistory of Japanese raw silk industry, Volume 1, The history of raw silk trade), Tokyo: Dainihon Sanshi Kai (The Silk
Industry Association of Japan).
Forslid, Rikard and Gianmarco I. P. Ottaviano (2003) “Analytically solvable core-periphery model”, Journal of Economic Geography, Vol. 3, pp. 229‑240.
Fujita, Masahisa and Paul Krugman (1995) “When is the economy monocentric?: von Thunen and Chamberlin
uniﬁed”, Regional Science and Urban economics, Vol. 25, pp. 505‑528.
Fujita, Masahisa, Paul Krugman and Tomoya Mori (1999) “On the evolution of hierarchical urban systems”, European Economic Review, Vol. 43, pp. 209‑251.
Fujita, Masahisa and Tomoya Mori (1997) “Structural stability and evolution of urban systems”, Regional Scienceand Urban Economics, Vol. 27, pp. 399‑442.
Krugman, Paul ( 1991 ) “Increasing returns and economic geography”, Journal of Political Economy, Vol. 99 , pp.
483‑499.
Ochiai, Isao (2007) Kinsei no chiikikeizai to shohin ryutsu (Regional economies and distribution in the pre-modern era), Tokyo: Iwata shoin.

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