Wilmar was the former name of a then-unincorporated district of San Gabriel Township in the San Gabriel Valley, about eight miles east of the center of Los Angeles.
[citation needed] Wilmar was combined with the unincorporated communities of Garvey (to the east of Wilmar) and Potrero Heights (to the south of Wilmar) to become the unincorporated community of South San Gabriel in the early 1950s.
Most of South San Gabriel was later annexed by the city of Rosemead (mostly during the mid-1960s), though parts of it were annexed by other adjacent cities and part of it remains unincorporated today.
The area of Wilmar known as Potrero Heights, south of the intersection of Del Mar and Graves Avenues, came to be known in the 1950s as Garvey Hills.
Later as the ethnicity of the area changed, it became home to the infamous Lomas gang, one of Los Angeles' earliest Hispanic gangs.