The siege at Yorktown lasted three weeks, beginning in late September 1781 and concluding with the surrender of British General Cornwallis on October 19, 1781.

During this crucial period, they were allowed American and French forces, led by General George Washington, to effectively coordinate their strategies and strengthen their positions against the British. The extended siege demonstrated the effectiveness of combined military efforts and showcased the importance of alliances in warfare. The successful siege not only resulted in a decisive American victory but also marked a pivotal turning point in the American Revolutionary War, significantly advancing the cause of independence.