Sir Geoffrey Rudolph Elton FBA (born Gottfried Rudolf Otto Ehrenberg) was a German-born British political and constitutional historian, specialising in the Tudor period. He taught at Clare College, Cambridge, and was the Regius Professor of Modern History there from 1983 to 1988. An strong advocate of the primacy of political and administrative history, Elton was the pre-eminent Tudor historian of his day. He also made very significant contributions to the then current debate on the philosophy of historical practice, as well as having a powerful effect on the profession through, among other things, his presidency of the Royal Historical Society.