José María Alvarado (1813–1846) was the son of Juan Bautista
Alvarado (a soldier and cousin to the governor by the same name)
and María Raimunda Yorba. José's grandfather, the elder Juan
Bautista Alvarado, accompanied Gaspar de Portolà as an enlisted
man in the Spanish Army in 1769. He married Lugarda Dionisia
Osuna, daughter of Juan María Osuna.
In 1840, Sgt. Alvarado was given a land grant to 8878-acre (36 km²)
Rancho Los Vallecitos de San Marcos by his cousin, Governor
Alvarado. The ranch was located in present San Marcos, California.
In 1842, Alvarado was Suplente (Substitute Justice of the Peace) of
San Diego.
During the Mexican-American War, Alvarado fought in the Battle of
San Pasqual. He later was one of 11 men captured by an Indian
band in the home of José Antonio Serrano, owner of Rancho
Pauma. They were taken to an Indian ranchería at Agua Caliente, on
Rancho San José, tortured, and killed. This was known as the
Pauma Massacre. His widow then sold their ranch with the
permission of her sons and later remarried.