Gaspar de Portolá was a Spanish explorer and military officer born in 1710. He is best known for leading the first overland expedition to California in 1769. Portolá aimed to establish Spanish missions and settlements in the region, which was largely uncharted at the time. During his expedition, Portolá founded the first European settlement in California, known as San Diego de Alcalá. He also explored the coastal areas and the San Francisco Bay. His efforts contributed significantly to the Spanish colonization of California and the establishment of the California Mission System.