St. Isidore Parish was established in 1921, the same year as Holy Family in Orange and St. Anne in Seal Beach.

Citizens of Los Alamitos had to use the general store or hotel for mass services before the opening of the church.

[3][4] In the late 1930s and early 40s, ten stained glass windows were added to the church.

However, it was closed again by the Roman Catholic Diocese of Orange in 1999, citing a lack of Spanish-speaking priests and the need to add expensive earthquake prevention measures to the church.

[1][2][3][5] Following fundraising, the church was bought by the St. Isidore Historical Plaza Organization, a volunteer community service group, in April 2014.

[8] Some elements used in the building of the church include "plastered walls, wood beams, wrought iron accents and ceramic tiles."

[1] Its foundation is made from wooden posts on concrete footings, the walls are stucco, and the roof is from terracotta.