This mesa was home to native American Indians long before Spaniards arrived in California. This site, along with nearby Fairview Park in Costa Mesa, is believed to be part of the historic village complex of Genga. The adobe displays artifacts from the Indian period.
Six Spanish leagues are located southeast of Mission San Juan Capistrano. It was founded in 1776. Fr. Zephyrin Engelhardt describes the adobe in Missions of San Juan Capistrano as a station of Mission located on the Santa Ana River.
The site was initially a settlement of Indians, which was occasionally visited by the Padres. Provision had to be made for sheltering the Capistrano cattle, who grazed on Costa Mesa in the 1800s. A small adobe was constructed to house the majordomo (and his men) between 1820-1823. The east and south walls contained the large “mission” bricks that made up this first structure.
The Mission Period ended, and the Spanish land grants became divided. Don Diego Sepulveda, an ex-alcalde of Pueblo de Los Angeles, took the adobe. It took its current form during the Sepulveda tenure. He made additions to the walls through the use of smaller ranch-type adobe blocks.
The Eduardo Pollereno and another adobe were then neighbors. Each was in prime locations on the mesa, each with its own water source. These were the last homes remaining in the area as late 1868. On a map of the year, the structure is called the “House of Diego Sepulveda”. It can be seen in the east room.
After the Dons’ era ended, there was a transition period. The adobe became part of a bigger, more sprawling ranch house. The adobe walls could be seen from the outside except for the east wall which was plastered. The west side of the building had a frame structure. The entire building was then housed under a high peaked roofing, which is responsible for the preservation and restoration of the old adobe walls.
Costa Mesa Post 455, American Legion held its first meeting at the adobe after the First World War. On the grounds of Harbor Rest Cemetery, now Harbor Lawn – Mount Olive, is the original flagpole that was erected by the Post.
The Segerstrom family purchased the property in 1940. In 1963, the Adobe and surrounding 5-acres were donated to Costa Mesa by the Segerstroms as a tribute to the early settlers of this area.