Centralist Republic of Mexico
Further Kumeyaay raids on El Cajon (1836) and Rancho Jamul (1837) threatened the security of San Diego, as many residents of San Diego fled the city. The Kumeyaay were able to attack San Diego in the late 1830's. Kumeyaay advancements into Rancho Bernardo in the North and San Ysidro and Tijuana to the South at the end of the decade threatened to cut off San Diego from the rest of the Centralist Republic of Mexico. The Kumeyaay made preparations to lay siege on San Diego in the early 1840s and launched a second attack on San Diego in June 1842. However, San Diego managed to defend itself once more. The Kumeyaay prevented Mexican usage of the ranchos around San Diego and evicted most of the Californios in the area by 1844, and continued launching raids deep into the Mexican controlled coast up until the start of the Mexican-American War.