William Frank Buckley Jr. (born William Francis Buckley; November 24, 1925 – February 27, 2008) was an American conservative writer, public intellectual, and political commentator. In 1955, he founded National Review, the magazine that stimulated the conservative movement in the mid-20th century United States. Buckley hosted 1,429 episodes of the public affairs television show Firing Line (1966–1999), the longest-running public affairs show with a single host in American television history, where he became known for his distinctive Mid-Atlantic accent and wide vocabulary.

Born in New York City, Buckley spoke Spanish as his first language before learning French and then English as a child. He served stateside in the United States Army during the Second World War. After the war, he attended Yale University, where he engaged in debate and right-wing political commentary. Afterward, he worked for two years in the Central Intelligence Agency. In addition to editorials in National Review, Buckley wrote God and Man at Yale (1951) and more than fifty other books on diverse topics, including writing, speaking, history, politics, and sailing. His works include a series of novels featuring fictitious CIA agent Blackford Oakes as well as a nationally syndicated newspaper column. Buckley's views varied, and are considered more complex between left and right than most conservative intellectuals today. His views on race rapidly changed from the 1950s to the 1960s, from endorsing Southern racism to positively anticipating the election of an African-American to the presidency.

Buckley called himself both a conservative and a libertarian. He is widely considered one of the most influential figures in the Conservative movement.