Richard Butler, 1st Earl of Glengall (13 November 1775 – 30 January 1819), known as Lord Cahir before 1816, was an Irish peer.
He was the son and heir of James Butler, 9th Baron Cahir and Sarah Nicholls. In July 1788 he succeeded to his father's title and assumed his seat in the Irish House of Lords. Following the implementation of the Acts of Union 1800, he was elected as one of the original 28 Irish representative peers, and took his seat on the Tory benches in the British House of Lords. On 22 January 1816 he was created Viscount Cahir and Earl of Glengall, both titles in the Peerage of Ireland.
Marriage and issue
On 15 August 1793, he married Emily Jefferyes, daughter of James St. John Jefferyes and Arabella FitzGibbon, sister of the first Earl of Clare. They had four children:
He was succeeded by his only son, Richard Butler.