Question: What is a historically significant part of a historical region of Silesia presently located in the Czech Republic that its area is 316.9 km2?

Context articles: Hlučín Region
Cieszyn Silesia
Silesia
Moravian dialects
Olomouc Region
Czech Silesia
Ostrava
Zlín Region
Moravian-Silesian Region
Czech Republic

Hlučín Region (Czech: "Hlučínsko" (familiarly "Prajzsko"), German: "Hultschiner Ländchen" , Polish: "Kraik hulczyński" ) is a historically significant part of Czech Silesia, today a part of the Moravian-Silesian Region in the Czech Republic, named after its largest town Hlučín.
 Its area is 316.9 km2 and in 2001 it had about 73,914 inhabitants.
Cieszyn Silesia or Těšín Silesia or Teschen Silesia (Polish:   , Czech:   or   , German: "Teschener Schlesien" or "Olsagebiet") is a historical region in south-eastern Silesia, centered on the towns of Cieszyn and Český Těšín and bisected by the Olza River.
 Since 1920 it has been divided between Poland and Czechoslovakia, and later the Czech Republic.
 It covers an area of about 2280 km2 and has about 810,000 inhabitants, of which 1002 km2 (44%) is in Poland, while 1280 km2 (56%) is in the Czech Republic.
Silesia ( ; Polish: "Śląsk" ; Czech: "Slezsko" ; German:    ] ; Silesian German: "Schläsing"; Silesian: "Ślůnsk" [ɕlonsk] ; Lower Sorbian: "Šlazyńska" ; Upper Sorbian: "Šleska" ; Latin: "Silesia" ) is a region of Central Europe located mostly in Poland, with small parts in the Czech Republic and Germany.
 Its area is about 40,000 km2 , and its population about 8,000,000.
 Silesia is located along the Oder River.
 It consists of Lower Silesia and Upper Silesia.
Moravian dialects (Czech: "moravská nářečí, moravština" ) are the varieties of Czech spoken in Moravia, a historical region in the southeast of the Czech Republic.
 There are more forms of the Czech language used in Moravia than in the rest of the Czech Republic.
 The main four groups of dialects are the Bohemian-Moravian group, the Central Moravian group, the Eastern Moravian group and the Lach (Silesian) group (which is also spoken in Czech Silesia).
 While the forms are generally viewed as regional variants of Czech, some Moravians (108,469 in the 2011 Census) claim them to be one separate Moravian language.
Olomouc Region (Czech: "Olomoucký kraj" ) is an administrative unit (Czech: "kraj" ) of the Czech Republic, located in the north-western and central part of its historical region of Moravia ("Morava") and in a small part of the historical region of Czech Silesia ("České Slezsko").
 It is named for its capital Olomouc.
Czech Silesia (Czech: "České Slezsko" ; Silesian: "Czeski Ślůnsk" ; German: "Tschechisch-Schlesien" ; Polish: "Śląsk Czeski" ) is the name given to the part of the historical region of Silesia presently located in the Czech Republic.
 While not today an administrative entity in itself, Czech Silesia is, together with Bohemia and Moravia, one of the three historical Czech lands.
 In this context, it is often mentioned as "Silesia" even though it is only around one tenth of the area of the historic land of Silesia.
Ostrava (Polish: "Ostrawa" , German: "Ostrau" or "Mährisch Ostrau") is a city in the north-east of the Czech Republic and is the capital of the Moravian-Silesian Region.
 It is 15 km from the border with Poland, at the meeting point of four rivers: the Odra, Opava, Ostravice and Lučina.
 In terms of both population and area Ostrava is the third largest city in the Czech Republic, the second largest city in Moravia, and the largest city in Czech Silesia; it straddles the border of the two historic provinces of Moravia and Silesia.
 The population was around 300,000 in 2013.
 The wider conurbation – which also includes the towns of Bohumín, Doubrava, Havířov, Karviná, Orlová, Petřvald and Rychvald – is home to around 500,000 people, making it the largest urban area in the Czech Republic apart from the capital, Prague.
Zlín Region (Czech: "Zlínský kraj" ) is an administrative unit (Czech: "kraj" ) of the Czech Republic, located in the central-eastern part of the historical region of Moravia.
 It is named after its capital Zlín.
 Together with the Olomouc Region it forms a cohesion area of Central Moravia.
 It is located in the eastern part of the Czech Republic, where the borders with Slovakia (Trenčín and Žilina Regions) are formed by its eastern edge.
 It borders with South Moravian Region in the southwest, Olomouc Region in the northwest and Moravian-Silesian Region in the north.
 Culturally, the region is composed of parts of three traditional Moravian regions: Hanakia, the Moravian Slovakia and the Moravian Wallachia, as the city of Zlín lies roughly at their tripoint.
The Moravian-Silesian Region (Czech: "Moravskoslezský kraj" ; Polish: "Kraj morawsko-śląski" ; Slovak: "Moravsko-sliezsky kraj" ), is one of the 14 administrative Regions of the Czech Republic.
 Before May 2001 it was called the Ostrava Region (Czech: "Ostravský kraj" ).
 The region is located in the north-eastern part of its historical region of Moravia and in most of the Czech part of the historical region of Silesia.
 The region borders the Olomouc Region to the west and the Zlín Region to the south.
 It also borders two other countries – Poland (Opole and Silesian Voivodeships) to the north and Slovakia (Žilina Region) to the east.
The Czech Republic ( Czech: "Česká republika" , ] ), also known as Czechia ( ; , ] ), is a nation state in Central Europe bordered by Germany to the west, Austria to the south, Slovakia to the east and Poland to the northeast.
 The Czech Republic covers an area of 78866 km2 with a mostly temperate continental climate and oceanic climate.
 It is a unitary parliamentary republic, has /1e6 round 1 million inhabitants and the capital and largest city is Prague, with over 1.2 million residents.
 The Czech Republic includes the historical territories of Bohemia, Moravia, and Czech Silesia.