In the 1700s the valley in which San Diego Country Estates is located received its name when Father Mariner of Mission San Diego de Alcalá discovered the location, proclaiming it a constant and beautiful valley, and named it in honor of Saint Vincent. As the area became colonized by the Spanish and later fell under Mexican jurisdiction, the land of the San Vicente Valley became a part of the Mexican land-grant known as Rancho Cañada de San Vicente y Mesa del Padre Barona in 1846. Under the grant prominent persons such as William Augustus Barnett and families, the Dukes, settled the region.