In 1783, San Juan was partitioned from Santa Ana but was still a "barrio" within the Province of Manila. The El Deposito reservoir was historically known as the site where the onset of the Philippine Revolution through the Battle of San Juan del Monte took place in 1896. The opening salvo against Spain took place in San Juan in 1897 when the Katipunan attacked the "alamacén" (armoury) or "polvorín" (gunpowder magazine) of the Spanish East Indies colonial government. The town was later incorporated into the Province of Rizal in 1901 under American military rule.