He was born and educated in Dublin, where he trained as a barrister and entered the Irish Parliament in 1775. A brilliant orator, he led the movement to repeal Poynings’ Law, which made all Irish legislation subject to the approval of the British Parliament. After considerable agitation the British government yielded and repealed the Act (1782). He also strongly opposed the Act of Union (1801), which merged the British and Irish parliaments. In 1806 he became member for Dublin in the British House of Commons and devoted the rest of his life to the cause of Catholic emancipation.