In which conflict did the First Caco War take place, as related to Marine Corps history?

The First Caco War occurred in Haiti from 1915 to 1916 and is significant in Marine Corps history due to the involvement of U.S. Marine Corps forces in the conflict. This war was fought between the Haitian government, supported by Haitian nationalists known as Cacos, and U.S. military forces. The U.S. intervention was prompted by political instability and concerns about foreign influence in Haiti. U.S. Marines played a crucial role in this conflict, where they were tasked with restoring order and establishing control over the country during a period of turmoil. This experience laid the groundwork for subsequent Marine Corps operations in the region and demonstrated the evolving role of the military in foreign interventions.

Given these historical contexts, Haiti is the correct answer as it directly relates to the First Caco War and the Marine Corps' involvement in international conflicts during that time.