List of Famous people born in Leinster, Ireland

Thomas MacDonald Patterson was an American politician and newspaper publisher who served as a member of the United States Senate and United States House of Representatives from Colorado.

St. Lorcán Ua Tuathail, known in English as Saint Laurence O'Toole and in French as St. Laurent d'Eu, was Archbishop of Dublin at the time of the Norman invasion of Ireland. St. Lorcán played a prominent role in the Irish Church Reform Movement of the 12th century and mediated between the parties during and after the invasion. He was canonised in 1225 by Pope Honorius III.

Donnchadh Mór Ó Dálaigh was a celebrated Irish poet, and master of the Irish classical style called Dán Díreach, who died in 1244. Mor is the Irish word for "great".

Peter Fintan Lalor was an Irish-Australian rebel and, later, politician who rose to fame for his leading role in the Eureka Rebellion, an event controversially identified with the "birth of democracy" in Australia.

James Hoban was an Irish architect, best known for designing the White House in Washington, D.C.

Eamonn Seán Duggan was an Irish lawyer and politician who served as Government Chief Whip and Parliamentary Secretary to the Minister for Defence from 1927 to 1932, Parliamentary Secretary to the Minister for Finance from 1926 to 1927, Parliamentary Secretary to the Executive Council from 1922 to 1926, Minister without portfolio September 1922 to December 1922 and Minister for Home Affairs January 1922 to September 1922. He served as a Teachta Dála (TD) from 1918 to 1933. He was a Senator for the University of Dublin from 1933 to 1936.

Eugene Casserly was an Irish-American journalist and lawyer. The son of Patrick S. Casserly, he served in the United States Senate from California.

James Geoghegan was an Irish Fianna Fáil politician, barrister and judge who served as a Judge of the Supreme Court from 1936 to 1950, Attorney General of Ireland from November 1936 to December 1936 and Minister for Justice from 1932 to 1933. He served as a Teachta Dála (TD) for the Longford–Westmeath constituency from 1930 to 1936.

Patrick Phelan, was a Canadian Roman Catholic priest, Sulpician, and Bishop of Kingston briefly in 1857.

John Cassidy was an Irish sculptor and painter who worked in Manchester, England, and created many public sculptures.