The Old Barracks Museum is among the more important historic sites in New Jersey. It was one of five military barracks built in New Jersey in the late 1750s to house British troops (in the winter) during the French and Indian War (1754-1763). None of the other barracks exist. As such, the barracks is the only extant and restored military building in the state dating to the colonial period. It is perhaps most famous for being site of the surprise attack on the night of December 25/26, 1776. The Continental Army, under the command of George Washington, attacked and captured the 1,000-strong Hessian (German) garrison stationed here in the battle known as the Battle of Trenton. The Americans suffered few casualties in the victory, which boosted morale and increased enlistment into the army. Visitors to the museum can immerse themselves in the history of the barracks through a variety of activities such as summer day camps and camp-ins for high school-age students. The barracks is a National Historic Landmark and has been a museum since 1914.
After the battle, the barracks became a hospital. A doctor named Dr. Bodo Otto performed smallpox inoculations, helping save the lives of soldiers who would otherwise have raised the already high number of deaths by disease (more soldiers died from disease than battle). This was the first mass medical treatment of soldiers in the Western Hemisphere. In later years the barracks became a residence for indigent widows, a single women's home, and boarding school. Trenton's first mayor also lived here. A portion of the barracks was demolished but the rest has been restored to what it likely appeared in Colonial times.