Nassau Hall, colloquially known as Old Nassau, is the oldest building at Princeton University in Princeton, Mercer County, New Jersey, United States. In 1783 it served as the United States Capitol building for four months. At the time it was built in 1756, Nassau Hall was the largest building in colonial New Jersey and the largest academic building in the American colonies.

The Battle of Princeton was a battle of the American Revolutionary War, fought near Princeton, New Jersey on January 3, 1777, and ending in a small victory for the Colonials. General Lord Cornwallis had left 1,400 British troops under the command of Lieutenant Colonel Charles Mawhood in Princeton. Following a surprise attack at Trenton early in the morning of December 26, 1776, General George Washington of the Continental Army decided to attack the British in New Jersey before entering the winter quarters. On December 30, he crossed the Delaware River back into New Jersey. His troops followed on January 3, 1777. Washington advanced to Princeton by a back road, where he pushed back a smaller British force but had to retreat before Cornwallis arrived with reinforcements. The battles of Trenton and Princeton were a boost to the morale of the patriot cause, leading many recruits to join the Continental Army in the spring.