John Edgar Hoover was an American law-enforcement administrator who served as the final Director of the Bureau of Investigation (BOI) and the first Director of the Federal Bureau of Investigation (FBI). President Calvin Coolidge first appointed Hoover as director of the BOI, the predecessor to the FBI, in 1924. After 11 years in the post, Hoover became instrumental in founding the FBI in June 1935, where he remained as director for an additional 37 years until his death in May 1972 – serving a total of 48 years leading both the BOI and the FBI and under eight Presidents.

The director of the Federal Bureau of Investigation is the head of the Federal Bureau of Investigation, a United States federal law enforcement agency, and is responsible for its day-to-day operations. The FBI director is appointed for a single 10-year term by the president of the United States and confirmed by the Senate. The FBI is an agency within the Department of Justice (DOJ), and thus the director reports to the attorney general of the United States.