What was Benjamin Franklin's role?

Benjamin Franklin's most decisive contribution to American independence was diplomatic: as American minister to France from 1776 to 1785 he secured the alliance, loans, supplies, and naval support without which the colonies could not have defeated Britain. Congress sent the 70 year old Franklin to France in October 1776, weeks after the Declaration of Independence and after a string of military defeats around New York City. He arrived in Paris in December 1776 with commissioners Silas Deane and Arthur Lee and quickly became the celebrity of French society, cultivating the image of a plain Quaker philosopher in fur cap and unpowdered hair.

The image was deliberate: French intellectuals admired his scientific work on electricity and the Enlightenment popularizers loved his proverbs, and Franklin used that fame to overcome the cautious calculation of foreign minister Charles Gravier, comte de Vergennes. France had been quietly funneling money and gunpowder to the colonies through the dummy company Rodrigue Hortalez et Compagnie since 1776, but full alliance required a colonial victory in the field. The American victory at Saratoga on October 17, 1777, in which General Horatio Gates accepted General John Burgoyne's surrender, gave Franklin his opening.

Vergennes feared that London would offer favorable terms and end the war, so France moved quickly. On February 6, 1778 Franklin and his French counterparts signed two treaties, the Treaty of Amity and Commerce establishing trade and recognizing American independence, and the Treaty of Alliance pledging French entry into the war if Britain attacked France. Spain joined in 1779, the Netherlands declared war on Britain in 1780, and the conflict became a global war.

France ultimately provided about 12,000 soldiers, most of the cash that kept the Continental Army paid, the cannon and muskets shipped through the Caribbean, and crucially the fleet under Comte de Grasse that bottled up the British army at Yorktown in October 1781. Franklin also helped negotiate the Treaty of Paris that ended the war, signed September 3, 1783 with John Adams and John Jay. American negotiators secured generous boundaries to the Mississippi River and from the Great Lakes to Spanish Florida, navigation rights on the Mississippi, and fishing rights off Newfoundland.

After the treaty, Franklin remained in France until 1785 raising additional loans. He returned to Philadelphia a national hero, having shaped the war's outcome from a Paris parlor as much as Washington shaped it from a Hudson Valley camp.