

ĭonald Bren, an urban planner who later became the president of the Irvine Company, drafted a master plan which placed roads in the valleys and houses on the hills, and contoured to the geography of the area. In 1960, early developers dismissed most of the land in Mission Viejo as simply "undevelopable". This city was one of the last regions of Orange County to be urbanized due to its geologic complexity. Mission Viejo was a hilly region primarily used as cattle and sheep grazing land, since it was of little use to farmers.

During the Mexican–American War, Forster provided fresh horses to United States military forces which were used on the march of San Diego to invade Los Angeles. Rancho Mission Viejo was purchased by Don Juan Forster, an English-born Mexican ranchero. History Don Juan Forster purchased Rancho Misión Vieja in 1845. The United States Census Bureau defines an urban area of Orange County cities not part of Los Angeles's urban area with Mission Viejo as the principal city: the Mission Viejo– Lake Forest– Laguna Niguel, CA urban area had a population of 646,843 as of the 2020 census, ranked 65th in the United States. The city's name is a reference to Rancho Mission Viejo, a large Spanish land grant from which the community was founded. The city is noted for its tree-lined neighborhoods, receiving recognition from the National Arbor Day Foundation. Mission Viejo is suburban in nature and culture, and consists of residential properties, offices and businesses. Mission Viejo is considered one of the largest master-planned communities ever built under a single project in the United States and is rivaled only by Highlands Ranch in size. Mission Viejo ( / v i ˈ eɪ h oʊ/ vee- AY-hoh corruption of Misión Vieja, Spanish for "Old Mission") is a commuter city in the Saddleback Valley in Orange County, California, United States.
