Civil war broke out in Nicaragua during the first months of 1926, and U.S. naval landing parties went ashore to establish a neutral zone for the protection of American citizens.
As the fighting intensified and spread, additional coastal enclaves were formed by the Navy to shelter refugees. By January 1927 the U.S. Special Service Squadron was reinforced by two light cruisers and seven destroyers.
When the danger points moved inland, 3,000 U.S. Marines supported by planes from Navy Observation Squadron 3 landed at the request of the Nicaraguan government. Once order was restored, sailors and Marines monitored free elections and organized and trained an efficient National Guard.