William Fife Knowland (June 26, 1908 – February 23, 1974) was an American politician, newspaper publisher, and Republican Party leader. He was a U.S. Senator representing California from 1945 to 1959. He was Senate Majority Leader from August 1953 to January 1955 after the death of Robert A. Taft. In 1958, he made a failed run for Governor of California.