Armed Forces Day, also known as Army Day, is observed in Nicaragua every May 27 as a public holiday. This day commemorates the establishment of the Nicaraguan armed forces, which began forming after the country gained independence in 1838 to protect against foreign invasions. The National Army of Nicaragua received its modern designation in 1995 when it transitioned to a professional army. Throughout its history, the Nicaraguan army has participated in significant military campaigns, including resisting the rule of William Walker from 1855 to 1857 and engaging in conflicts with Costa Rica and the Dominican Republic. As of 2011, the armed forces comprised approximately 12,000 personnel, including members of the Army, Air Force, and Navy. The observance of this day highlights the importance of the military in Nicaragua's history and national identity.