Starting in 1848, after the Mexican–American War, Pío Pico began acquiring the 10,000-acre (4,000 ha) Rancho Paso de Bartolo, and built a home in 1853.

The structure was completely redone into its current form, adding American-style elements into the traditional Californio design.

By 1898 the City of Whittier began buying up parts of the property to construct a water pumping facility.

In 1907, local Whittier citizens, led by Harriet Williams Russell Strong, were able to have the site made a historic monument.

Finally, in 1996 a Los Angeles County proposition earmarked US$2.5 million for the park's restoration.

At the re-opening ceremonies, the Battle of Rio San Gabriel, which occurred nearby during the Mexican–American War, was re-enacted.