The Cheviot Hills area was shifting from agricultural to residential use when the City of Los Angeles brought the territory within its limits by annexation. On May 16, 1923, the “Ambassador Addition” formally added previously unincorporated County land, much of it the former Rancho Rincón de los Bueyes, to the city. It was the second try. On October 10, 1922, the City Council had rejected the first annexation petition (along with Laurel Canyon’s) because “the petitions did not include the districts’ sharing in the carrying charges of the recently approved $12,000,000 sewer bond issue.” On March 20, 1923, electors in the new territory chose to join Los Angeles, and the City Council annexed it the next day.
The “Ambassador” name likely came from the fact that a large section in the northwest held the Ambassador Hotel’s golf course, which had opened on the land in July 1921. Ambassador was also used for the July 1923 Ambassador Park subdivision in the northeast portion of the former Rancho la Ballona – an area already annexed to Los Angeles with the May 22, 1915, Palms Annexation.
In the far left, Lot A (Tract No. 843) of José de Arnaz’ subdivision of Rancho Rincón de los Bueyes became the larger section of the Country Club Highlands subdivision. Immediately east, Arnaz’ Lots B and C were the Ambassador Hotel’s Rancho Country Club, while Lot D and the northern portion of Lot E were Hillcrest Country Club. Below them, most of Lot E of Arnaz’ earlier subdivision became the Monte Mar Vista subdivision. To the west, Tract 1938, a subdivision of Francisco Higuera’s Lot A in the Rancho Rincón de los Bueyes, would become the Cheviot Hills subdivision. To its right, the Tract of Francisco Higuera held the California Country Club, now the California Country Club Estates tract. And further right is Tract 3494, a portion of which (Lot 19, where the numbers 3494 appear) would hold the California Country Club clubhouse and caddy shack. Most of the rest of Tract 3494 would be Castle Heights, where Culver City founder Harry Culver would build his estate.