We believe that IRV leads to 2-party domination. Is Ireland evidence for that? Well, since 1921, Ireland's Dail has been elected by means of 3-to-5-winner multiwinner reweighted STV PR elections, not IRV. So Ireland cannot really be used to study IRV per se, and we would expect it to be a multiparty country.
However, Ireland's president really is elected by IRV (the single-winner special case of STV). That does not matter terribly much because the Irish president is a largely ceremonial position whose only real power worth mentioning is her ability to refer a bill to the supreme court for the purpose of testing its constitutionality. (The most powerful person is the PM.)
Anyhow, for whatever it is worth, so far every Irish president has been from one of two parties. In fact they have all been from just one party (Fianna Fail) except for Mary Robinson. The fact that she was able to win without the support of Fianna Fail for the only time in Irish history, was a single-time aberration perhaps related to her worldwide fame (e.g. she won the Nobel Peace Prize), the fact the FF candidate was linked to scandals, and the unusual absence of a credible contender from the Fine Gael party. (Analysis)
| Years | President | Party |
|---|---|---|
| 1938 – 1945 | Douglas Hyde | (all) |
| 1945 – 1959 | Sean Thomas O'Kelly | FF |
| 1959 – 1973 | Eamon de Valera | FF |
| 1973 – 1974 | Erskin Childers | FF |
| 1974 – 1976 | Cearbhall O'Dalaigh | FF |
| 1976 – 1990 | Patrick Hillery | FF |
| 1990 – 1997 | Mary Robinson | Labour |
| 1997 – | Mary McAleese | FF |
As a country with proportional representation based on reweighted STV, one would expect Ireland to be a multiparty country. However, perhaps because Ireland also features IRV (single winner special case of STV) elections, that causes it to be more 2-party dominated.
| %Seats | Party |
|---|---|
| 41.5 | Fianna Fail |
| 22.5 | Fine Gael |
| 10.8 | Labour |
| 6.5 | Sinn Fein |
| 4.0 | Progressive Democrats |
| 3.8 | Green Party |
| <0.8% each | Socialists and others |
| Years | Prime Minister | Party |
|---|---|---|
| 1932 – 1948 | Eamon de Valera | FF |
| 1948 – 1951 | John Costello | FG |
| 1951 – 1954 | Eamon de Valera | FF |
| 1954 – 1957 | John Costello | FG |
| 1957 – 1959 | Eamon de Valera | FF |
| 1959 – 1966 | Sean Lemass | FF |
| 1966 – 1973 | Jack Lynch | FF |
| 1973 – 1977 | Liam Cosgrave | FG |
| 1977 – 1979 | Jack Lynch | FF |
| 1979 – 1981 | Charles Haughey | FF |
| 1981 – 1982 | Garret FitzGerald | FG |
| 1982 | Charles Haughey | FF |
| 1982 – 1987 | Garret FitzGerald | FG |
| 1992 – 1994 | Albert Reynolds | FF |
| 1994 – 1997 | John Bruton | FG |
| 1997 – | Bertie Ahern | FF |