Roman Catholic Diocese of Oakland
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![Cathedral of Christ the Light, Oakland](/Images/godic/202501/15/Oak_Cathdrl_14431.jpg")
![Mission San José is the seat of the first parish.](/Images/godic/202501/15/MissionSanJoseCA.LYH4431.jpg")
The Roman Catholic Diocese of Oakland (Latin:Dioecesis Quercopolitana) is an ecclesiastical territory or diocese of the Roman Catholic Church in Northern California. The diocese comprises Alameda and Contra Costa Counties in the San Francisco Bay Area. The Cathedral of Christ the Light serves as the bishop's seat, replacing the Cathedral of Saint Francis de Sales which was demolished after the Loma Prieta earthquake of 1989.