San Jose, California Wikipedia. San Jose, officially San José (/ ˌ s æ n h oʊ ˈ z eɪ,ˈ s eɪ /; Spanish: [saŋ xoˈse]; Spanish for ''Saint Joseph''), is a major city in the state of California that is the cultural, financial, and political center of Silicon Valley and largest city in Northern California by both population and area.