

In high school, he acquired the nickname Willem, the Dutch version of the name William.

During an interview, he said that half of his family puts the emphasis on the first syllable of the surname while the other half emphasizes the second syllable. His surname, Dafoe, is the English version of the Swiss surname Thévou. He recalled in 2009, "My five sisters raised me because my father was a surgeon, my mother was a nurse and they worked together, so I didn't see either of them much." His brother, Donald, is a surgeon and research scientist. He has five sisters and two brothers and is of English, French, German, Irish, and Scottish descent. William James Dafoe was born on July 22, 1955, in Appleton, Wisconsin, the son of Muriel Isabel (née Sprissler 1922–2012) and Dr.
