Sir Keith Vivian Thomas CH FBA FRHistS FLSW (born 2 January 1933) is a Welsh historian. His area of focus is the history of the early modern world. He is best known for writing Religion and the Decline of Magic and Man and the Natural World. From 1986 to 2000, he was president of Corpus Christi College, Oxford.
Thomas was born in Wick, Glamorgan.[1] He is married to Lady Valerie Thomas and has two children.