On October 26, 1776, exactly one month to the day after being named an agent of a diplomatic commission by the Continental Congress, Benjamin Franklin sets sail from Philadelphia for France, with which he was to negotiate and secure a formal alliance and treaty.
In France, the accomplished Franklin was feted throughout scientific and literary circles and he quickly became a fixture in high society. While his personal achievements were celebrated, Franklin's diplomatic success in France was slow in coming. Although it had been secretly aiding the Patriot cause since the outbreak of the American Revolution, France felt it could not openly declare a formal allegiance with the United States until they were assured of an American victory over the British.
For the next year, Franklin made friends with influential officials throughout France, while continuing to push for a formal alliance. France continued to secretly support the Patriot cause with shipments of war supplies, but it was not until the American victory over the British at the Battle of Saratoga in October 1777 that France felt an American victory in the war was possible.
A few short months after the Battle of Saratoga, representatives of the United States and France, including Benjamin Franklin, officially declared an alliance by signing the Treaty of Amity and Commerce and the Treaty of Alliance on February 6, 1778. The French aid that these agreements guaranteed was crucial to the eventual American victory over the British in the War for Independence.