Keene was the eldest son of Rt. Rev.
Edmund Keene,
Bishop of Ely, and his wife Mary Andrews, daughter. of Lancelot Andrews of Edmonton. His uncle,
Sir Benjamin Keene, MP was ambassador to Madrid. Keene was educated at
Eton College from 1762 to 1770 and was admitted at
Gray's Inn in 1767 and at
Peterhouse, Cambridge on 6 October 1770. In 1774 he was awarded MA at Cambridge. He married Mary Ruck, daughter of George Ruck of Swyncombe, Oxfordshire on 18 March 1780, and succeeded his father in July 1780. ==Political career==