Sebastian Vizcaino was the Spanish explorer who founded San Diego, California, on Nov. 10, 1602. He chose the name San Diego as it was both the name of the expedition's flagship and for the holiday, the Feast of San Diego de Alcalá, traditionally held on Nov. 12.
Vizcaino is believed to have been born around 1548, and he died around 1629. The bulk of his exploring occurred from 1602 to 1603. Vizcaino discovered Monterey Bay and named it after Don Gaspár de Zúñiga y Acevedo, Count of Monte Rey. Additionally, he accurately charted portions of the Pacific coast. Some of his maps would be used until 1790.