# South Mayo (UK Parliament constituency)

South Mayo was a parliamentary constituency in Ireland, which returned one Member of Parliament (MP) to the House of Commons of the Parliament of the United Kingdom, elected on a system of first-past-the-post, from 1885 to 1922.
Prior to the 1885 general election the area was part of the two-seat Mayo constituency. From 1922, on the establishment of the Irish Free State, it was not represented in the UK Parliament.

## Boundaries

This constituency comprised the southern part of County Mayo. In 1918, the constituency expanded to take in the district electoral divisions of Ballinchalla and Owenbrin from County Galway which had been transferred into County Mayo under the 1898 Local Government Act.
1885–1918: The baronies of Clanmorris and Kilmaine, that part of the barony of Costello contained within the parishes of Aghamore, Annagh, Bekan and Knock, and that part of the barony of Carra contained within the parish of Ballyovey.
1918–1922: The existing South Mayo constituency together with that part of the Connemara constituency contained in the administrative county of Mayo.

## Members of Parliament

| Years | Member | Party |
| 1885–1890 | J. F. X. O'Brien | Irish Parliamentary Party |
| 1891–1895 | J. F. X. O'Brien | Irish National Federation |
| 1895–1900 | Michael Davitt | Irish National Federation |
| 1900 – January 1910 | John O'Donnell | Irish Parliamentary Party |
| January–December 1910 | John O'Donnell | All-for-Ireland League |
| 1910–1918 | John Fitzgibbon | Irish Parliamentary Party |
| 1918–1922 | William Sears | Sinn Féin |

## Elections
### Elections in the 1880s

General election 27 November 1885: South Mayo :
| Party | Party | Candidate | Votes | % | ±% |
| | Irish Parliamentary | J. F. X. O'Brien | 4,953 | 98.5 | |
| | Irish Conservative | George Orme Malley | 75 | 1.5 | |
| Majority | Majority | Majority | 4,878 | 97.0 | |
| Turnout | Turnout | Turnout | 5,028 | 63.0 | |
| Registered electors | Registered electors | Registered electors | 7,980 | | |
| | Irish Parliamentary win (new seat) | Irish Parliamentary win (new seat) | Irish Parliamentary win (new seat) | Irish Parliamentary win (new seat) | Irish Parliamentary win (new seat) |
General election 6 July 1886: South Mayo :
| Party | Party | Candidate | Votes | % | ±% |
| | Irish Parliamentary | J. F. X. O'Brien | Unopposed | Unopposed | Unopposed |
| Registered electors | Registered electors | Registered electors | 7,980 | | |
| | Irish Parliamentary hold | Irish Parliamentary hold | Irish Parliamentary hold | Irish Parliamentary hold | Irish Parliamentary hold |

### Elections in the 1890s

General election 13 July 1892: South Mayo :
| Party | Party | Candidate | Votes | % | ±% |
| | Irish National Federation | J. F. X. O'Brien | Unopposed | Unopposed | Unopposed |
| Registered electors | Registered electors | Registered electors | 9,723 | | |
| | Irish National Federation gain from Irish Parliamentary | Irish National Federation gain from Irish Parliamentary | Irish National Federation gain from Irish Parliamentary | Irish National Federation gain from Irish Parliamentary | Irish National Federation gain from Irish Parliamentary |
General election 19 July 1895: South Mayo :
| Party | Party | Candidate | Votes | % | ±% |
| | Irish National Federation | Michael Davitt | Unopposed | Unopposed | Unopposed |
| Registered electors | Registered electors | Registered electors | 10,033 | | |
| | Irish National Federation hold | Irish National Federation hold | Irish National Federation hold | Irish National Federation hold | Irish National Federation hold |

### Elections in the 1900s

South Mayo by-election 28 February 1900 :
| Party | Party | Candidate | Votes | % | ±% |
| | Irish Parliamentary | John O'Donnell | 2,401 | 84.9 | N/A |
| | Ind. Nationalist | John MacBride | 427 | 15.1 | New |
| Majority | Majority | Majority | 1,974 | 69.8 | N/A |
| Turnout | Turnout | Turnout | 2,828 | 31.2 | N/A |
| Registered electors | Registered electors | Registered electors | 9,055 | | |
| | Irish Parliamentary hold | Irish Parliamentary hold | Swing | N/A | |
General election 3 October 1900: South Mayo :
| Party | Party | Candidate | Votes | % | ±% |
| | Irish Parliamentary | John O'Donnell | Unopposed | Unopposed | Unopposed |
| Registered electors | Registered electors | Registered electors | 9,055 | | |
| | Irish Parliamentary hold | Irish Parliamentary hold | Irish Parliamentary hold | Irish Parliamentary hold | Irish Parliamentary hold |
General election 3 October 1906: South Mayo :
| Party | Party | Candidate | Votes | % | ±% |
| | Irish Parliamentary | John O'Donnell | Unopposed | Unopposed | Unopposed |
| Registered electors | Registered electors | Registered electors | 8,110 | | |
| | Irish Parliamentary hold | Irish Parliamentary hold | Irish Parliamentary hold | Irish Parliamentary hold | Irish Parliamentary hold |

### Elections in the 1910s

January 1910 general election: South Mayo :
| Party | Party | Candidate | Votes | % | ±% |
| | All-for-Ireland | John O'Donnell | 2,667 | 54.5 | N/A |
| | Irish Parliamentary | Conor O'Kelly | 2,226 | 45.5 | N/A |
| Majority | Majority | Majority | 441 | 9.0 | N/A |
| Turnout | Turnout | Turnout | 4,893 | 62.1 | N/A |
| Registered electors | Registered electors | Registered electors | 7,883 | | |
| | All-for-Ireland gain from Irish Parliamentary | All-for-Ireland gain from Irish Parliamentary | Swing | N/A | |
December 1910 general election: South Mayo :
| Party | Party | Candidate | Votes | % | ±% |
| | Irish Parliamentary | John Fitzgibbon | Unopposed | Unopposed | Unopposed |
| Registered electors | Registered electors | Registered electors | 7,883 | | |
| | Irish Parliamentary gain from All-for-Ireland | Irish Parliamentary gain from All-for-Ireland | Irish Parliamentary gain from All-for-Ireland | Irish Parliamentary gain from All-for-Ireland | Irish Parliamentary gain from All-for-Ireland |
1918 general election: South Mayo :
| Party | Party | Candidate | Votes | % | ±% |
| | Sinn Féin | William Sears | Unopposed | Unopposed | Unopposed |
| Registered electors | Registered electors | Registered electors | 21,567 | | |
| | Sinn Féin gain from Irish Parliamentary | Sinn Féin gain from Irish Parliamentary | Sinn Féin gain from Irish Parliamentary | Sinn Féin gain from Irish Parliamentary | Sinn Féin gain from Irish Parliamentary |