The Foothill League is one of the earliest CIF-SS leagues in existence. Membership has historically included schools throughout Los Angeles County, including in the Santa Clarita Valley, Burbank, Glendale, and the San Gabriel Valley.[3] In the 1930s, the league's footprint extended as far south as Fullerton.[4]
In 2006, Burbank and Burroughs high schools in Burbank left the Foothill League to join the Pacific League to reduce travel expenses and become more competitive.[2] Since then, the Foothill League has been composed exclusively of Hart District schools.