Defeat of the Filibusterer: William Walker and the 2nd Battle of Rivas (1856)

In the decades before the American Civil War, several (mostly southern-born) filibusterers – those who wage illegal, extra-national invasions of other countries – led expeditions to conquer Mexico and several Central American republics. The hope, for some of these filibusterers, was to create new slave states to add to the union. Perhaps the most famous adventurer was William Walker, who led numerous attempts – some temporarily successful – to seize Nicaragua.

Walker gathered an army of a few thousand white southerners who were quite enthusiastic about his cause. They had initial success and Walker had himself “elected” president. Nevertheless, his relatively untrained army was plagued by cholera and mass desertions which thinned his ranks. Fearing that Walker’s army would grow too strong and might spread its area of conquest, Costa Rican President Mora declared war, not on Nicaragua as a whole, but on Walker’s filibusterer usurpers.

Walker wasted no time and immediately invaded Costa Rica itself. In response, the Costa Rican president accompanied the 8,000 man army himself to meet Walker’s invasion, though his brother was in direct military command. On March 20, Mora and 3,000 Costa Ricans attacked and surprised a small force of filibusterers under the inexperienced commander, COL Louis Schlessinger – who had failed to post sentries or conduct reconnaissance. After hearing word of this defeat, Walker led his main army south to recapture the city of Rivas. He’d soon find that the Costa Ricans were ready for him.

In brutal street-to-street fighting, Walker’s men gained small successes and an initial stalemate, but they were ultimately outnumbered and overwhelmed. With many filibusterers now gathered in a key building – El Meson de Guerra – a Costa Rican drummer boy volunteered to torch the thatched roof of the building. This dislodged the filibusterers, although the boy was killed in the process. That night, Walker’s outmatched force slipped out of town and retreated north. Some Costa Rican commanders wanted to pursue, but President Mora paused to bury the dead and deal with a cholera outbreak in camp.

At the cost of 170 casualties (including 130 dead) in his small army, Walker had inflicted only 60 casualties on the Costa Rican force. Walker would continue to fight coalitions of Central American states for three more years until he was finally captured, and executed, by a Honduran force.