Frank A. DeSimone was an American mobster who was boss of the Los Angeles crime family from 1956 to 1967. DeSimone was the son of former don Rosario DeSimone. He was sometime referred to as "One Eye" because one of his eyes drooped. Frank DeSimone's nephew, Thomas DeSimone, was an enforcer for the Lucchese crime family in New York City. He was also related to Simone Scozzari and Joseph Civello.

The Los Angeles crime family, also known as the L.A. Mafia or the Southern California crime family, and dubbed "the Mickey Mouse Mafia" by former Los Angeles Police Chief Daryl Gates, is an Italian-American organized crime syndicate based in Los Angeles as part of the larger Italian-American Mafia. Since its inception in the early 20th century, it has spread throughout Southern California. Like most Mafia families in the United States, the Los Angeles crime family gained wealth and power through bootlegging alcohol during the Prohibition era. The L.A. family reached its peak strength in the 1940s and early 1950s under Jack Dragna, although the family was never larger than the New York or Chicago families. The Los Angeles crime family itself has been on a gradual decline, with the Chicago Outfit representing them on The Commission since the death of boss Jack Dragna in 1956.