France was the first foreign government to recognize the U.S. as a sovereign power.
The 13 American colonies severed their political connections to Great Britain by issuing the Declaration of Independence, adopted by the Continental Congress on July 4, 1776. The Declaration summarized the colonists’ motivations for seeking independence. But the Declaration’s most important diplomatic effect was to allow for recognition of the United States by friendly foreign governments. By declaring themselves an independent nation, the American colonists were able to confirm an official alliance with the Government of France and obtain French assistance in the war against Great Britain. France was the most obvious potential ally, which was a long-time enemy of Britain and a colonial rival who had lost much of their lands in the Americas after the French and Indian War. Britain's victory in the Seven Years' War had shifted the European balance of power and so France had been planning for a war of revenge since the Treaty of Paris that had ended the conflict in 1763. But Congress had to wait until the 1778 Treaty of Alliance with France for a formal recognition of U.S. independence.
On March 17, 1778, four days after a French ambassador informed the British government that France had officially recognized the U.S. as an independent nation, Great Britain declared war on France, thereby engaging France in the American Revolutionary War. French entry into the war would lead to further escalation of the war when Spain entered the fight against Britain as France's ally.