William August Bartholomae, Jr. (January 23, 1893 – January 5, 1964) was an American sailor and oil tycoon. He competed in the mixed 6 metres at the 1936 Summer Olympics. Bartholomae, the stepfather of fellow competitor Carl Paul, was stabbed to death by Manola Gallardo, the sister of his sister-in-law Mrs. Charles Bartholomae in 1964.