Rancho San Mateo

[2] Pio Pico, the last governor of California under Mexican rule, made the grant to his secretary, Cayetano Arenas of the Pueblo de Los Ángeles, for his family’s service to the government.

Arenas sold the property in 1846 to Yerba Buena (Pueblo de San Francisco) merchant and American immigrant William Davis Merry Howard.

Howard with his wife, Agnes, retired from the city to live on the rancho in 1854, and built a residence named "El Cerrito" and developed a successful working ranch.

With the cession of California to the United States following the Mexican-American War, the 1848 Treaty of Guadalupe Hidalgo provided that the land grants would be honored.

In 1861, Henry F. Teschemacher and Joseph P. Thompson were opposed in an important court case concerning the Rancho San Mateo patent and land under water at high tide.