During the existence of the Irish Free State (6 December, 1922 - 29 December, 1937) the head of government was known as the President of the Executive Council.
William T Cosgrave
Image: W T Cosgrave
(Born in Dublin on June 6, 1880 - November 16, 1965.) Was the first President of the Executive Council of the Irish Free State (October 1922 - March 1932). Having joined the Irish Volunteers in 1913, he fought under Eamonn Ceannt in the 1916 Rising.
He was a Sinn Féin MP for Kilkenny in 1918. He was a member of the first Dáil as Minister for Local Government. He supported the Anglo-Irish Treaty of 1921 and became leader of the Cumann na nGaedhael Government when Sinn Féin divided after the 1921 Treaty was signed.
He served briefly as Minister for Finance and Minister for Defence in 1924. Following the defeat of Cumann na nGaedhael in the 1932 general election, he led the Opposition in Dáil Éireann. He retired from politics in 1945.
Eamon de Valera
Image: Eamon De Valera
(Born in New York on October 14, 1882 - August 29, 1975.) He joined the Irish Volunteers in 1913. He was a Commandant in the 1916 Rising occupying Boland's Mill, he was court-martialled and sentenced to death, the sentence however, was commuted to life imprisonment.
Following a reprieve, he was released in 1917 and was chosen as Sinn Féin representative for East Clare. In 1917 he was made President of Sinn Féin. In May 1918, de Valera was imprisoned in Lincoln jail for his part in orchestrating public outcry against the British governments extension of conscription to Ireland.
He escaped from Lincoln jail and on April 1, 1919, was unanimously elected by the first Dáil as president. He ardently opposed the Anglo-Irish Treaty of 1921. In 1926 he founded the Fianna Fáil party.
He was made President of the Executive Council in 1932. After 16 years of government, he was voted out of office in 1948 but returned for two further terms as Taoiseach (1951-54 and 1957-59). In 1959 he was elected President of Ireland and re-elected in 1966 for a further seven years.
John A Costello
Image: John A. Costello
(Born in Dublin on June 20, 1891 - January 5, 1976.) Was Attorney General from 1926-1932. In 1948 he became Taoiseach of Ireland's first interparty government (comprising of Fine Gael, Labour, Clann na Talmhúain and Clann na Pobhlachta).
This government continued in office until its dissolution in May 1951. He again headed a coalition government in 1954 (comprising of the same parties as above), which was dissolved in 1957.
Image: Sean Lemass
(Born in Dublin on July 15, 1899 - May 11, 1971.) He joined the Irish Volunteers when he was 15. He took part in the 1916 Rising; in 1920 he was interned in Ballykinler. He opposed the Anglo-Irish Treaty of 1921.
He fought in the Civil War and was interned in the Curragh Camp and Mountjoy jail from December 1922-December 1923. In 1925 he was elected Sinn Féin representative for Dublin. A founding member of the Fianna Fáil party, he became Minister for Industry and Commerce from 1932-1948.
He was Minister for Supplies during the Emergency. He was made Tanaiste in 1945. In 1959 he succeeded de Valera as Taoiseach. He continued in office until his resignation in November 1966.
Image: Jack Lynch
(Born in Cork on August 15, 1917 - October 20, 1999.) He was returned as Fianna Fáil representative for Cork city in 1948. He was Minister for Lands from 1951-1954: Minister for the Gaeltacht in 1957, Minister for Education 1957-1959, Minister for Industry and Commerce 1959-1965 and Minister for Finance 1965-1966.
In 1966 he was made Taoiseach and Leader of Fianna Fáil, positions he held until March 1973. In the general election of 1977 he led Fianna Fáil in a landslide victory and again became Taoiseach until 1979 when he stepped down from office.
Image: Liam Cosgrave
(Born in Dublin on April 13, 1920 - 4 October, 2017.) The son of WT Cosgrave, he was elected to the Dáil in 1943. He served in both the interparty governments of 1948 and 1954, as Parliamentary Secretary to the Taoiseach and to the Minister for Industry and Commerce (1948).
He was Minister for External Affairs from 1954-1957. In 1966, he was made leader of Fine Gael. He became Taoiseach and leader of the coalition government (Fine Gael and Labour), in 1973 until 1977 when he resigned as leader.
Charles J Haughey
Image: Charles Haughey
(Born in Mayo on September 16, 1925 - 13 June, 2006.) He joined Fianna Fáil in 1948. He represented different constituencies and served as Parliamentary Secretary to the Minister for Justice from 1960-1961.
He was made Minister for Justice in 1961. From 1964 to 1966, he served as Minister for Agriculture and Fisheries and as Minister for Finance from 1966-1970. He was in Opposition from 1975 - 1977 and in June 1977, was appointed Minister for Health and Social Welfare. On 11 December, 1979, he succeeded Jack Lynch as Taoiseach and leader of the Fianna Fáil party until June 1981.
He again served as Taoiseach from March 1982 - December 82 and March 1987 - February 1992. On 12 July, 1989, he led Fianna Fáil into its first coalition government (with the Progressive Democrats). He resigned from office in 1992.
Image: Garret Fitzgerald
(Born in Dublin on February 9, 1926 - 19 May, 2011.) He became a senator in 1965. He was returned as Fine Gael representative for Dublin South East in 1969 and served as Opposition spokesman on education (1969 - 1972) and on finance (1972 - 1973). He became Minister for Foreign Affairs in the coalition government of 1973 (Fine Gael and Labour).
He was elected leader of Fine Gael in 1977.
He served as Taoiseach from 30 June, 1981- 9 March, 1982, and again from 14 December, 1982 - 10 March, 1987. In 1992 he retired from politics.
Image: Albert Reynolds
(Born in Roscommon on November 3, 1932 - 21 August, 2014.) He first entered national politics in 1977 as a Fianna Fáil representative for Longford-Westmeath. He served as Minister for Industry and Energy from March to December 1982. From 1979-1981 he served as Minister for Posts and Telegraphs and Minister for Transport.
He was Minister for Industry and Commerce in 1987. In 1988 he was appointed Minister for Finance and remained in that office until February 1992, when he was elected Taoiseach. He retired as Taoiseach in December 1994.
Image: John Bruton
(Born in Dublin on 18 May, 1947.) He was elected to the Dáil to represent Meath in 1969. He was Parliamentary Secretary to the Minister for Education from 1973 - 1977 and to the Minister for Industry and Commerce from 1975 - 1977. He served as Minister for Finance from June 1981 - March 1982 and Minister for Industry, Trade, Commerce and Tourism from 1983-1986.
From February 1986 - March 1987 he was Minister for Finance and from January 1987- March 1987, served as Minister for the Public Service. He was elected Taoiseach of the coalition government (Fine Gael, Labour and Democratic Left) of 1994-1997. He was leader of Fine Gael from 1990 to 31 January, 2001.
He was re-elected to the Dáil in May 2002. He resigned his seat in the Dáil on 31 October, 2004, and was appointed as the EU Ambassador to the United States on 24 November, 2004.
Image: Bertie Ahern
(Born in Dublin on 12 September, 1951.) He was educated at St Aidan's CBS in Whitehall and then studied at the College of Commerce in Rathmines. He was first elected to Dáil Éireann in 1977 and was returned to the Dáil at each subsequent election. He served as the Assistant Whip between 1980 and 1981.
Then he was appointed as the Minister of State at the Department of the Taoiseach and Government Chief Whip and at the Department of Defence. Between 1986 and 1987, he served as the Lord Mayor of Dublin. He was the Minister for Labour between 1987 and 1991.
He served then as the Minister for Finance between 1991 and 1994. On 19 November, 1994, he was elected as leader of the Fianna Fáil party. Having successfully contested the general election in 1997, Bertie Ahern became the 11th Taoiseach and resigned on 6 May, 2008.
Image: Brian Cowen
(Born in Offaly on 10 January, 1960.) He was educated at Clara National School and at the Cistercian College of Mount St Joseph, Roscrea. He studied law at University College Dublin and practised as a solicitor from October 1983 until becoming a government minister in 1992.
He was first elected to Dáil Éireann in 1984, in a byelection precipitated by the death of his father, becoming at the age of 24 the youngest member of the 24th Dáil.
Appointed Minister for Labour in February 1992, he was Minister for Transport, Energy and Communications from January 1993 to December 1994. He was appointed Minister for Health in June 1997 and was Minister for Foreign Affairs from January 2000 to June 2002. He remained Minister for Foreign Affairs after the general election in 2002, becoming Minister for Finance in September 2004. He was appointed Tánaiste after the 2007 general election and continued as Minister for Finance from June 2007 to May 2008.
Following the resignation of Bertie Ahern, Brian Cowen became the 12th Taoiseach on 7 May, 2008, and served until 9 March, 2011.
Image: Enda Kenny
(1951 - Born in Islandeady, Co. Mayo.) He was educated at St Gerald's College, Castlebar and at St Patrick's College, Drumcondra, Dublin. He worked as a primary teacher before being elected to Dáil Éireann in 1975 at a bye-election brought about by the death of his father. At 24, he was the youngest member of the 20th Dáil.
He was returned to the Dáil in each of the subsequent 12 general elections. In February 1986 he was appointed Minister of State at the Departments of Education and Labour, in a government led by Garrett Fitzgerald. In December 1994 he was appointed Minister for Tourism and Trade in a government led by John Bruton.
He became leader of Fine Gael in 2002, and served in that capacity until 2017. Following the general election of February 2011 he was nominated, by Dáil Éireann, as Taoiseach on 9 March 2011 and served in that capacity until, following the general election of February 2016, he was again nominated Taoiseach on 6 May 2016.
He presided as President of the EU Council from January to June 2016. He retired as Taoiseach with effect from 14 June 2017. As Taoiseach he held the Defence portfolio, from May to July 2014, and again from May 2016 until his retirement in June 2017. He was the first Fine Gael Leader to be returned to government on successive occasions.