saac Butt (1813-79) was a strong unionist who, as a result of the Great Famine, became a federalist and advocated a parliament in Dublin to legislate on purely Irish matters. As a barrister, he defended members of Young Ireland after the 1848 Rising and members of the Irish Republican Brotherhood (The Fenians) between 1865 and 1867. He was president of the Amnesty Association, created in 1868 to campaign for the release of the Fenians who were imprisoned in harsh conditions after the 1867 Rising. In 1870 he founded the Home Government Association with the intention of achieving a federal system of government. 

It contained Catholics and Protestants, Orangemen and Repealers, Liberals and Conservatives and a few Fenians and Young Irelanders. It was succeeded in 1873 by the Home Rule League, also founded by Butt. In the general election of 1874, the League secured 59 seats—the first step in the evolution of the Irish Parliamentary Party.