It became a global war
From the beginning both British and American leaders knew that they would need assistance from foreign powers to successfully prosecute the war. England did not maintain a large standing army and its Hanoverian King sought the assistance of mercenaries from several German states to augment his troops. German troops came from several provinces and principalities, paid for by the British Crown and collectively called Hessians.
American diplomats were sent to France to acquire help from England’s old enemy, and their efforts paid off almost immediately, although initial French aid was covert, funded secretively and privately. After the American victory at Saratoga French assistance became more open. France recognized the United States (the second nation to do so after Morocco) and entered into a military alliance. Spain and the Netherlands soon followed.
Besides the French assistance in North America and the Caribbean, with its Navy successfully countering the British fleet, the war entered the Mediterranean and the Indian Ocean. France was a rival with England for colonies on the Indian subcontinent, and the war which began at Lexington Green now raged at places with exotic names such as Porto Novo and Trincomalee. Hyder Aly, ruler of Mysore, became a combatant in the war which began as the American Revolution.
Spain besieged the English stronghold at Gibraltar and invaded and secured Minorca. Dutch troops fought the British in India and Central America, as well as on several Caribbean islands. Spanish troops captured Mobile, in what is now Alabama, and parts of Florida. The British, with so many of its troops tied down in North America by Washington’s army, were stretched thin defending their Empire from their Continental rivals.
None of the European nations which sided with the Americans achieved all of their aims in the war. Spain failed to capture Gibraltar, a longtime goal of the Spanish Court. France emerged from the war heavily in debt and with its lower classes rife with egalitarian fervor. The Dutch lost most of their Caribbean colonies. War in India would continue for many years. Only the United States emerged from the conflict with all of its war aims fulfilled, independent and with access to the mineral and natural wealth of a continent.