Fort Ticonderoga’s capture in 1775 gave the American revolutionary cause valuable artillery before the Declaration of Independence. Ethan Allen and Benedict Arnold led the surprise attack on May 10, 1775, taking the fort from its small British garrison.
The fort controlled a strategic route between Lake Champlain and the Hudson River. Its captured cannons were later transported to Boston by Henry Knox during the winter of 1775–1776. Washington placed those guns on Dorchester Heights, forcing British troops to evacuate Boston in March 1776.
Ticonderoga’s capture was one of the first offensive actions by American forces after fighting began at Lexington and Concord. The fort changed hands several times during the war and was eventually abandoned by the British in 1777. It is not the same site as Fort McHenry, whose defense inspired the U.S. national anthem decades later.