# Merthyr Tydfil (UK Parliament constituency)

Merthyr Tydfil was a parliamentary constituency centred on the town of Merthyr Tydfil in Glamorgan. From 1832 to 1868 it returned one Member of Parliament (MP) to the House of Commons of the Parliament of the United Kingdom, and in 1868 this was increased to two members. The two-member constituency was abolished for the 1918 general election.
A single-member constituency (known as Merthyr) existed from 1918 until 1945 and, by the 1950 general election, it had been renamed Merthyr Tydfil. The constituency was abolished for the 1983 general election, when it was largely replaced by the new Merthyr Tydfil and Rhymney constituency.

## History

Merthyr was regarded as a Liberal seat throughout the nineteenth century and particularly after the landmark election of 1868. There were tensions within the constituency, however and these were manifested by the rivalry between Merthyr and Aberdare, which became more pronounced as the latter grew in importance after 1850. Increasingly, also, the constituency was affected by the debate about working-class representation. Thomas Halliday contested Merthyr as a 'labour' candidate as early as 1874 and the return of Keir Hardie in 1900 was a notable landmark in the growth of the Labour Party. From 1922 onwards, Merthyr was a safe Labour seat.

## 1832–1867

The Reform Act 1832 was the first significant review of the arrangements for the election of MPs to the House of Commons, Patterns of representation had remained essentially unchanged for centuries and no recognition was given to the growth of urban settlements in the wake of the industrial revolution. The discontent of the late 1820s, culminating in serious disturbances in 1831, including the Merthyr Rising persuaded the government to take action in favour of reform. Within the Reform Act 1832 the one significant change in Wales was the carving out of a new parliamentary constituency, centred at Merthyr Tydfil, from the county of Glamorgan.
The Parliamentary Boundaries Act 1832 defined the new Parliamentary Borough of Merthyr Tydvil in great detail:

### Electoral politics 1832–1867

When the constituency was established the vast majority of the electorate were resident in Merthyr Tydfil and its environs, such as the industrial township of Dowlais. In contrast the electorate of the neighbouring Aberdare Valley was relatively small, numbering 3,691 compared with 22,083 in Merthyr. The first member for Merthyr Tydfil was Sir Josiah John Guest who served, albeit with some opposition until his death in 1852.
Guest was succeeded by Henry Austin Bruce who, again, served with little opposition until the Reform Act 1867. Bruce was a prominent Liberal although associated with the less radical wing of the Liberal Party and was criticised for his role in events such as the 1857 Aberdare Strike.

## 1867–1918

The Representation of the People Act 1867, which increased the number of members returned to two, also widened the constituency boundaries. To the existing parliamentary borough were added some additional parts of the parish of Aberdare, part of the parishes of Merthyr and "Faenor" (Vaynor), and part of the district of Mountain Ash.
The same boundaries were retained in 1885, and can be seen on the boundary commissioners' map.

### 1868 general election

Merthyr Tydfil saw one of the most remarkable contests of the 1868 general election. Resulting directly from a tenfold increase in the electorate. Henry Richard was returned at the expense of the sitting member, Henry Austin Bruce.
Bruce had served as member since 1832 and his position was secure until the reforms of 1867. Even thereafter, the immediate interest appeared to be in who would occupy the second seat rather than whether or nor Bruce would be re-elected. The Merthyr element of the constituency had dominated the representation since its formation in 1832 but in recent years the population of the neighbouring Aberdare valley had grown considerably, mainly as a result of the development of the steam coal trade, that they should determine the identity of the second member. The Merthyr electorate had traditionally been far larger than that of Aberdare but by 1868, Aberdare's electorate formed almost half the total (11,446 in Aberdare; 13,329 in Merthyr). As a result, there was a widespread view amongst the industrialists and tradesmen of the Aberdare Valley that they should have a say in the selection of a second Liberal candidate to contest the seat alongside Bruce.
These commercial interests of the Aberdare Valley soon became allied with the powerful nonconformist interest, which was led by the key figure of Thomas Price, minister of Calfaria, Aberdare. Price, and other nonconformist ministers, were considered to have considerable influence over the largely chapel-going industrial workers who had been newly enfranchised. During 1867 these groupings rallied around Richard Fothergill, owner of the Aberdare Ironworks and also a figure of some influence in Merthyr due to his ownership of the Plymouth Ironworks. It was confidently expected that Fothergill would be returned alongside Bruce.
This remained the position until Henry Richard entered the fray in the summer of 1868. Richard's candidature was also opposed by members of the Irish community, on account of alleged comments by Richard about the Pope during a speech at Brecon.

### 1868–1888

Richard and Fothergill were re-elected in 1874. By 1879, however, Fothergill was in financial difficulties and there were calls for him to step aside. A deputation of tradesmen and working men who attended a meeting at Swansea to request to offer himself once again as a candidate but he eventually declined. He was replaced by Charles Herbert James. member of a long-standing politically active family in Merthyr. Both served until 1888 when Richard died and James stood down, leading to two by-elections within a twelve-month period. These led to the return of David Alfred Thomas and William Pritchard Morgan. Thomas and Morgan had much in common. Both were nonconformists, both were wealthy industrialists and both placed Welsh issues high on their list of political priorities. However, they also shared 'a hearty loathing' for each other.
Morgan's return, in particular, was significant, as he defeated Foulkes Griffiths, the official candidate of the Liberal Association. The result was also regarded as a defeat for the Cymru Fydd element in the Welsh Liberal Party. The Merthyr Liberal Association broke up after this election and did not function again until 1909.

### 1888–1918

Relations between Thomas and Morgan were not good, leading ultimately to a Liberal split which contributed to the success of Keir Hardie at the 1900 general election. For the first decade of the twentieth century Merthyr was represented by the unusual combination of David Alfred Thomas and Hardie. In 1910, Thomas chose to contest Cardiff instead and was succeeded by Sir Edgar Jones.

## 1918–1950

The two-member Merthyr Boroughs constituency was replaced at the 1918 general election by two separate constituencies, Aberdare and Merthyr Tydfil.

## 1950–1983

Merthyr Tydfil Borough Constituency, created by the Representation of the People Act 1948, had an identical area to the County Borough of Merthyr Tydfil. The seat was first contested at the 1950 general election. The boundaries were unchanged until 1983.

## Members of Parliament
### MPs 1832–1868

| Election | Member | Party |
| 1832 | Sir John Josiah Guest | Whig |
| 1852 | Henry Bruce | Peelite |
| 1859 | Henry Bruce | Liberal |
| 1868 | representation increased to two members | representation increased to two members |

### MPs 1868–1918

| Election | 1st Member | 1st Member | 1st Party | 2nd Member | 2nd Member | 2nd Party |
| 1868 | | Henry Richard | Liberal | | Richard Fothergill | Liberal |
| 1880 | | Henry Richard | Liberal | | Charles James | Liberal |
| 1888 by-election (Mar) | | Henry Richard | Liberal | | D. A. Thomas | Liberal |
| 1888 by-election (Oct) | | William Pritchard-Morgan | Liberal | | D. A. Thomas | Liberal |
| 1900 | | Keir Hardie | Labour | | D. A. Thomas | Liberal |
| 1910 (Jan) | | Keir Hardie | Labour | | Sir Edgar Jones | Liberal |
| 1915 by-election | | Charles Stanton | Ind. Labour | | Sir Edgar Jones | Liberal |
| 1918 | constituency abolished: see Merthyr and Aberdare | constituency abolished: see Merthyr and Aberdare | constituency abolished: see Merthyr and Aberdare | constituency abolished: see Merthyr and Aberdare | constituency abolished: see Merthyr and Aberdare | constituency abolished: see Merthyr and Aberdare |

### MPs 1950–1983

| Election | Election | Member | Party |
| 1950 | 1950 | constituency re-established | constituency re-established |
| | 1950 | S. O. Davies | Labour |
| | 1970 | S. O. Davies | Independent Labour |
| | 1972 by-election | Ted Rowlands | Labour |
| | 1983 | constituency abolished: see Merthyr Tydfil & Rhymney | constituency abolished: see Merthyr Tydfil & Rhymney |

## Elections 1832–1867
### Elections in the 1830s

General election 1832: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % |
| | Whig | John Josiah Guest | Unopposed | Unopposed |
| Registered electors | Registered electors | Registered electors | 502 | |
| | Whig win (new seat) | Whig win (new seat) | Whig win (new seat) | Whig win (new seat) |
General election 1835: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % |
| | Whig | John Josiah Guest | Unopposed | Unopposed |
| Registered electors | Registered electors | Registered electors | 561 | |
| | Whig hold | Whig hold | Whig hold | Whig hold |
General election 1837: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % |
| | Whig | John Josiah Guest | 309 | 69.6 |
| | Conservative | John Bruce Bruce | 135 | 30.4 |
| Majority | Majority | Majority | 174 | 39.2 |
| Turnout | Turnout | Turnout | 444 | 76.3 |
| Registered electors | Registered electors | Registered electors | 582 | |
| | Whig hold | Whig hold | Whig hold | Whig hold |

### Elections in the 1840s

General election 1841: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % | ±% |
| | Whig | John Josiah Guest | Unopposed | Unopposed | Unopposed |
| Registered electors | Registered electors | Registered electors | 776 | | |
| | Whig hold | Whig hold | Whig hold | Whig hold | Whig hold |
General election 1847: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % | ±% |
| | Whig | John Josiah Guest | Unopposed | Unopposed | Unopposed |
| Registered electors | Registered electors | Registered electors | 822 | | |
| | Whig hold | Whig hold | Whig hold | Whig hold | Whig hold |

### Elections in the 1850s

General election 1852: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % | ±% |
| | Whig | John Josiah Guest | Unopposed | Unopposed | Unopposed |
| Registered electors | Registered electors | Registered electors | 938 | | |
| | Whig hold | Whig hold | Whig hold | Whig hold | Whig hold |
Guest's death caused a by-election.
By-election, 14 December 1852: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % | ±% |
| | Peelite | Henry Bruce | Unopposed | Unopposed | Unopposed |
| | Peelite gain from Whig | Peelite gain from Whig | Peelite gain from Whig | Peelite gain from Whig | Peelite gain from Whig |
General election 1857: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % | ±% |
| | Peelite | Henry Bruce | Unopposed | Unopposed | Unopposed |
| Registered electors | Registered electors | Registered electors | 1,263 | | |
| | Peelite gain from Whig | Peelite gain from Whig | Peelite gain from Whig | Peelite gain from Whig | Peelite gain from Whig |
General election 1859: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % | ±% |
| | Liberal | Henry Bruce | 800 | 88.3 | N/A |
| | Liberal | Edward Merrick Elderton | 106 | 11.7 | N/A |
| Majority | Majority | Majority | 694 | 76.6 | N/A |
| Turnout | Turnout | Turnout | 906 | 67.2 | N/A |
| Registered electors | Registered electors | Registered electors | 1,349 | | |
| | Liberal hold | Liberal hold | Swing | N/A | |

### Elections in the 1860s

Bruce was appointed Vice-President of the Committee of the Privy Council for Education, requiring a by-election.
By-election, 25 April 1864: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % | ±% |
| | Liberal | Henry Bruce | Unopposed | Unopposed | Unopposed |
| | Liberal hold | Liberal hold | Liberal hold | Liberal hold | Liberal hold |
General election 1865: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % | ±% |
| | Liberal | Henry Bruce | Unopposed | Unopposed | Unopposed |
| Registered electors | Registered electors | Registered electors | 1,387 | | |
| | Liberal hold | Liberal hold | Liberal hold | Liberal hold | Liberal hold |

## Elections 1868–1918
### Elections in the 1860s

Seat increased to two members
General election 1868: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % | ±% |
| | Liberal | Henry Richard | 11,683 | 46.9 | N/A |
| | Liberal | Richard Fothergill | 7,439 | 29.9 | N/A |
| | Liberal | Henry Bruce | 5,776 | 23.2 | N/A |
| Majority | Majority | Majority | 1,663 | 6.7 | N/A |
| Turnout | Turnout | Turnout | 12,449 (est) | 85.4 (est) | N/A |
| Registered electors | Registered electors | Registered electors | 14,577 | | |
| | Liberal hold | Liberal hold | Swing | N/A | |
| | Liberal win (new seat) | Liberal win (new seat) | Liberal win (new seat) | Liberal win (new seat) | Liberal win (new seat) |

### Elections in the 1870s

General election 1874: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % | ±% |
| | Liberal | Henry Richard | 7,606 | 39.2 | −7.7 |
| | Liberal | Richard Fothergill | 6,908 | 35.6 | +5.7 |
| | Lib-Lab | Thomas Halliday | 4,912 | 25.3 | N/A |
| Majority | Majority | Majority | 1,996 | 10.3 | +3.6 |
| Turnout | Turnout | Turnout | 9,713 (est) | 63.0 (est) | −22.4 |
| Registered electors | Registered electors | Registered electors | 15,429 | | |
| | Liberal hold | Liberal hold | Swing | | |
| | Liberal hold | Liberal hold | Swing | | |

### Elections in the 1880s

General election 1880: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % | ±% |
| | Liberal | Henry Richard | 8,033 | 40.2 | +1.0 |
| | Liberal | Charles James | 7,526 | 37.6 | +2.0 |
| | Conservative | William Lewis | 4,445 | 22.2 | New |
| Majority | Majority | Majority | 3,081 | 15.4 | +5.1 |
| Turnout | Turnout | Turnout | 12,478 (est) | 87.5 (est) | +24.5 |
| Registered electors | Registered electors | Registered electors | 14,259 | | |
| | Liberal hold | Liberal hold | Swing | | |
| | Liberal hold | Liberal hold | Swing | | |
General election 1885: Merthyr Tydfil :
| Party | Candidate | Votes | % | ±% |
| Liberal | Henry Richard | Unopposed | Unopposed | Unopposed |
| Liberal | Charles James | Unopposed | Unopposed | Unopposed |
| Liberal hold | Liberal hold | Liberal hold | Liberal hold | Liberal hold |
| Liberal hold | Liberal hold | Liberal hold | Liberal hold | Liberal hold |
General election 1886: Merthyr Tydfil :
| Party | Candidate | Votes | % | ±% |
| Liberal | Henry Richard | Unopposed | Unopposed | Unopposed |
| Liberal | Charles James | Unopposed | Unopposed | Unopposed |
| Liberal hold | Liberal hold | Liberal hold | Liberal hold | Liberal hold |
| Liberal hold | Liberal hold | Liberal hold | Liberal hold | Liberal hold |
James resigned, causing a by-election.
By-election, 14 Mar 1888: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % | ±% |
| | Liberal | D. A. Thomas | Unopposed | Unopposed | Unopposed |
| | Liberal hold | Liberal hold | Liberal hold | Liberal hold | Liberal hold |
Richard died, causing a by-election.
By-election, 26 Oct 1888: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % | ±% |
| | Independent Liberal | William Pritchard-Morgan | 7,149 | 59.1 | New |
| | Liberal | Richard Foulkes Griffiths | 4,956 | 40.9 | N/A |
| Majority | Majority | Majority | 2,193 | 18.2 | N/A |
| Turnout | Turnout | Turnout | 12,105 | 78.5 | N/A |
| Registered electors | Registered electors | Registered electors | 15,411 | | |
| | Liberal hold | Liberal hold | Swing | N/A | |

### Elections in the 1890s

General election 1892: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % | ±% |
| | Liberal | D. A. Thomas | 11,948 | 45.9 | N/A |
| | Liberal | William Pritchard-Morgan | 11,756 | 45.2 | N/A |
| | Conservative | Benjamin Francis Williams | 2,304 | 8.9 | New |
| Majority | Majority | Majority | 9,452 | 36.3 | N/A |
| Turnout | Turnout | Turnout | 14,093 (est) | 81.6 | N/A |
| Registered electors | Registered electors | Registered electors | 17,271 | | |
| | Liberal hold | Liberal hold | Swing | N/A | |
| | Liberal hold | Liberal hold | Swing | N/A | |
General election 1895: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % | ±% |
| | Liberal | D. A. Thomas | 9,250 | 37.1 | −8.8 |
| | Liberal | William Pritchard-Morgan | 8,554 | 34.2 | −11.0 |
| | Conservative | Herbert Clark Lewis, 2nd Baron Merthyr | 6,525 | 26.1 | +17.2 |
| | Independent Liberal-Labour | Allen Upward | 659 | 2.6 | New |
| Majority | Majority | Majority | 2,029 | 8.1 | −28.2 |
| Turnout | Turnout | Turnout | 14,998 (est) | 88.1 | +6.5 |
| Registered electors | Registered electors | Registered electors | 17,024 | | |
| | Liberal hold | Liberal hold | Swing | −13.0 | |
| | Liberal hold | Liberal hold | Swing | −14.1 | |

### Elections in the 1900s

General election 1900: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % | ±% |
| | Liberal | D. A. Thomas | 8,598 | 46.9 | +9.8 |
| | Labour Repr. Cmte. | Keir Hardie | 5,745 | 31.3 | New |
| | Liberal | William Pritchard-Morgan | 4,004 | 21.8 | −12.4 |
| Majority | Majority | Majority | 1,741 | 9.5 | N/A |
| Turnout | Turnout | Turnout | 18,347 | 73.9 | −14.2 |
| Registered electors | Registered electors | Registered electors | 15,400 | | |
| | Liberal hold | Liberal hold | Swing | | |
| | Labour Repr. Cmte. gain from Liberal | Labour Repr. Cmte. gain from Liberal | Swing | | |
General election 1906: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % | ±% |
| | Liberal | D. A. Thomas | 13,971 | 43.7 | −3.2 |
| | Labour Repr. Cmte. | Keir Hardie | 10,187 | 31.9 | +0.6 |
| | Liberal | Henry Radcliffe | 7,776 | 24.4 | +2.6 |
| Majority | Majority | Majority | 2,411 | 7.5 | −2.0 |
| Turnout | Turnout | Turnout | 31,934 | 84.9 | +11.0 |
| Registered electors | Registered electors | Registered electors | 21,438 | | |
| | Liberal hold | Liberal hold | Swing | −1.9 | |
| | Labour Repr. Cmte. hold | Labour Repr. Cmte. hold | Swing | +1.9 | |

### Elections in the 1910s

General election January 1910: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % | ±% |
| | Liberal | Edgar Jones | 15,448 | 41.0 | −2.7 |
| | Labour | Keir Hardie | 13,841 | 36.7 | +4.8 |
| | Conservative | Arthur Fox-Davies | 4,756 | 12.6 | New |
| | Independent Liberal | William Pritchard-Morgan | 3,639 | 9.7 | New |
| Majority | Majority | Majority | 10,692 | 28.4 | +9.1 |
| Majority | Majority | Majority | 9,085 | 24.1 | +16.6 |
| Turnout | Turnout | Turnout | 37,684 | 93.0 | +8.1 |
| | Labour hold | Labour hold | Swing | | |
| | Liberal hold | Liberal hold | Swing | | |
General election, December 1910: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % | ±% |
| | Liberal | Edgar Jones | 12,258 | 42.2 | +1.2 |
| | Labour | Keir Hardie | 11,507 | 39.6 | +2.9 |
| | Liberal Unionist | John Henry Watts | 5,277 | 18.2 | +5.6 |
| Majority | Majority | Majority | 6,981 | 24.0 | −4.4 |
| Majority | Majority | Majority | 6,230 | 21.4 | −2.7 |
| Turnout | Turnout | Turnout | 29.042 | 81.3 | −11.7 |
| | Liberal hold | Liberal hold | Swing | | |
| | Labour hold | Labour hold | Swing | | |
1915 Merthyr Tydfil by-election :
| Party | Party | Candidate | Votes | % | ±% |
| | Independent Labour | Charles Stanton | 10,286 | 62.8 | New |
| | Labour | James Winstone | 6,080 | 37.2 | −2.4 |
| Majority | Majority | Majority | 4,206 | 25.6 | N/A |
| Turnout | Turnout | Turnout | 16,366 | 67.7 | −13.6 |
| | Independent Labour gain from Labour | Independent Labour gain from Labour | Swing | | |

## Elections 1950–1979
### 1950s

General election 1950: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % |
| | Labour | S. O. Davies | 29,210 | 78.91 |
| | Conservative | LF Haddrill | 6,294 | 17.00 |
| | Ind. Nationalist | Trefor Morgan | 1,511 | 4.08 |
| Majority | Majority | Majority | 22,916 | 61.91 |
| Turnout | Turnout | Turnout | 37,015 | 85.77 |
| | Labour hold | Labour hold | Swing | |
General election 1951: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % |
| | Labour | S. O. Davies | 28,841 | 79.57 |
| | Conservative | James F Lynam | 7,405 | 20.43 |
| Majority | Majority | Majority | 21,436 | 59.14 |
| Turnout | Turnout | Turnout | 36,246 | 84.42 |
| | Labour hold | Labour hold | Swing | |
General election 1955: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % |
| | Labour | S. O. Davies | 25,630 | 77.25 |
| | Conservative | Anthony Arnold | 7,548 | 22.75 |
| Majority | Majority | Majority | 18,082 | 54.50 |
| Turnout | Turnout | Turnout | 33,178 | 77.28 |
| | Labour hold | Labour hold | Swing | |
General election 1959: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % |
| | Labour | S. O. Davies | 26,608 | 77.14 |
| | Conservative | Miranda MM Greenaway | 7,885 | 22.86 |
| Majority | Majority | Majority | 18,723 | 54.28 |
| Turnout | Turnout | Turnout | 34,493 | 81.83 |
| | Labour hold | Labour hold | Swing | |

### 1960s

General election 1964: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % | ±% |
| | Labour | S. O. Davies | 23,275 | 75.27 | |
| | Conservative | Sidney W Doxsey | 4,767 | 15.42 | |
| | Plaid Cymru | Ioan Bowen Rees | 2,878 | 9.31 | New |
| Majority | Majority | Majority | 18,508 | 59.85 | |
| Turnout | Turnout | Turnout | 30,920 | 76.27 | |
| | Labour hold | Labour hold | Swing | | |
General election 1966: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % |
| | Labour | S. O. Davies | 21,737 | 74.49 |
| | Conservative | Gerald L Preece | 4,082 | 13.99 |
| | Plaid Cymru | Meic Stephens | 3,361 | 11.52 |
| Majority | Majority | Majority | 17,655 | 60.50 |
| Turnout | Turnout | Turnout | 29,180 | 73.92 |
| | Labour hold | Labour hold | Swing | |

### 1970s

General election 1970: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % | ±% |
| | Independent Labour | S. O. Davies | 16,701 | 51.90 | N/A |
| | Labour | Taliesin J Lloyd | 9,234 | 28.69 | −45.80 |
| | Conservative | Edward Jones | 3,169 | 9.85 | −4.14 |
| | Plaid Cymru | Chris Rees | 3,076 | 9.56 | −1.96 |
| Majority | Majority | Majority | 7,467 | 23.21 | N/A |
| Turnout | Turnout | Turnout | 32,180 | 77.92 | +4.00 |
| | Independent Labour gain from Labour | Independent Labour gain from Labour | Swing | +40.30 | |
NB: Davies claimed to be 83 in 1970 and his Constituency Labour Party felt that he was too old and ought to stand down. They thus de-selected him in favour of a younger man. However, although his true birth date is unconfirmed, Davies was undoubtedly several years older than he claimed, and was probably close to 90 years old when he fought and won the election as an Independent.
1972 Merthyr Tydfil by-election :
| Party | Party | Candidate | Votes | % | ±% |
| | Labour | Edward Rowlands | 15,562 | 48.58 | +19.89 |
| | Plaid Cymru | Emrys Roberts | 11,852 | 37.00 | +27.44 |
| | Conservative | Christopher Barr | 2,336 | 7.29 | −2.56 |
| | Communist | Arthur Lewis Jones | 1,519 | 4.74 | New |
| | Liberal | Angus Donaldson | 765 | 2.39 | New |
| Majority | Majority | Majority | 3,710 | 11.58 | N/A |
| Turnout | Turnout | Turnout | 32,034 | 79.5 | −1.6 |
| | Labour gain from Independent Labour | Labour gain from Independent Labour | Swing | | |
General election February 1974: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % | ±% |
| | Labour | Edward Rowlands | 20,486 | 64.07 | |
| | Plaid Cymru | Emrys Roberts | 7,336 | 22.94 | |
| | Conservative | Michael Knowles | 2,622 | 8.20 | |
| | Liberal | D Bettell-Higgins | 1,002 | 3.13 | |
| | Communist | A Jones | 369 | 1.15 | N/A |
| | Workers Revolutionary | R Battersby | 160 | 0.50 | New |
| Majority | Majority | Majority | 13,150 | 41.13 | |
| Turnout | Turnout | Turnout | 32,015 | 81.06 | |
| | Labour gain from Independent | Labour gain from Independent | Swing | | |
General election October 1974: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % |
| | Labour | Edward Rowlands | 21,260 | 70.61 |
| | Plaid Cymru | Emrys Roberts | 4,455 | 14.80 |
| | Conservative | LJ Walters | 2,587 | 8.59 |
| | Liberal | D Bettall-Higgins | 1,300 | 4.32 |
| | Communist | T Roberts | 509 | 1.69 |
| Majority | Majority | Majority | 16,805 | 55.81 |
| Turnout | Turnout | Turnout | 30,111 | 75.82 |
| | Labour hold | Labour hold | Swing | |
General election 1979: Merthyr Tydfil :
| Party | Party | Candidate | Votes | % | ±% |
| | Labour | Edward Rowlands | 22,386 | 71.32 | |
| | Conservative | AR de Wilde | 4,426 | 14.10 | |
| | Plaid Cymru | Eurfyl ap Gwilym | 2,962 | 9.44 | |
| | Liberal | RD Oliver | 1,275 | 4.06 | |
| | Communist | CC Dennett | 223 | 0.71 | |
| | Workers Revolutionary | GT Gould | 114 | 0.36 | New |
| Majority | Majority | Majority | 17,960 | 57.22 | |
| Turnout | Turnout | Turnout | 31,386 | 79.10 | |
| | Labour hold | Labour hold | Swing | | |