Sheldon Vanauken (/vəˈnɔːkən/;[1] August 4, 1914 – October 18, 1996) was an American author, best known for his autobiographical book A Severe Mercy (1977), which recounts his and his wife's friendship with C. S. Lewis, their conversion to Christianity, and dealing with tragedy. He published a sequel in 1985 titled Under the Mercy.