Longfellow House–Washington's Headquarters National Historic Site

The Longfellow House–Washington's Headquarters National Historic Site (also known as the Vassall-Craigie-Longfellow House and, until December 2010, Longfellow National Historic Site) is a historic site located at 105 Brattle Street in Cambridge, Massachusetts. It was the home of noted American poet Henry Wadsworth Longfellow for almost 50 years, and it had previously served as the headquarters of General George Washington during the early American Revolutionary War.

The house was built in 1759 for Jamaican plantation owner John Vassall Jr., who fled the Cambridge area at the beginning of the American Revolutionary War because of his loyalty to the king of England. George Washington occupied it as his headquarters beginning on July 16, 1775, and it served as his base of operations during the Siege of Boston until he moved out on April 4, 1776. Andrew Craigie, Washington's Apothecary General, was the next person to own the home for a significant period of time. He purchased the house in 1791 and instigated its only major addition. Craigie's financial situation at the time of his death in 1819 forced his widow Elizabeth to take in boarders, and one of those boarders was Henry Wadsworth Longfellow. He became its owner in 1843 when his father-in-law Nathan Appleton purchased it as a wedding gift. He lived in the home until his death in 1882.

The last family to live in the home was the Longfellow family, who established the Longfellow Trust in 1913 for its preservation. In 1972, the home and all of its furnishings were donated to the National Park Service, and it is open to the public seasonally. It presents an example of mid-Georgian architecture style.