The First Battle of Southern California was fought between the Dixie Republic and the United States.
After the countries of the former Confederacy conjoined and re-united to form the Dixie Republic, Dixie-inspired rebellions in southern California, Arizona and Nevada ran amok.
The Southern California Army, although initially fighting independently, soon became backed by the Dixie Republic, who sent them weapons, ammunition, money and gold, and the government in Richmond soon regarded as them as a part of the western flank of the Dixie Republic's military forces.
The Dixie Republic fought both United States government forces, and other Californian seperatist forces, and Republic of California, however the Dixie Republic also supported northern seperatists, due to them sharing conservative, Christian and right-wing ideologies.
The Dixie Republic was not interested in the Los Angeles area, only the southern areas of California.