The treaty that officially ended the American Revolutionary War is the Treaty of Paris, which was signed on September 3, 1783. This treaty was crucial as it recognized the independence of the thirteen American colonies from British rule and established the boundaries of the new nation. The agreement defined territories to the west, north, and south of the newly formed United States, setting the stage for future expansion. Additionally, both British and American interests were addressed, as British loyalists were granted certain protections regarding property and debts. The Treaty of Paris remains a foundational document for American diplomacy.