Between 1850 and 1857 six separate filibustering attempts left from San Francisco in hopes of conquest in Sonora, Mexico. Three U.S. citizens and three Frenchmen, all being drawn to California during the gold rush, failed to have their fortunes materialize. These adventurers desired more than California could offer and each organized groups to travel south in search of land, fame, and fortune in the northern Mexican state. Each group had its own motivations and designs on Sonora. Some simply wanted to colonize, others to conquer, but each failed in their attempts. In a time when all of Mexico, including Sonora, was suffering from political division and turmoil, these foreigners believed they could take advantage of the situation. In each instance, the Mexicans were able to maintain their soil and deal with the invaders. As each new filibusterer arrived, the Mexicans increased the aggression of their response, leading to military engagements in which men on both sides gave their lives. The battles would not be the end of the violence. After the fifth filibustering attempt, Mexico executed its leader, Raousset-Boulbon. Ongoing filibustering prodded Mexico into increasing levels of violence to quell these invasions. Filibustering concluded in 1857, when the Mexicans battled with the Crabb Expedition, forcing its surrender. Finally, Henry A. Crabb and all his men, save one, were executed on the orders of the local military commander to send a message to all future filibusters that they would be dealt with similarly.
