The American Revolution (1775-1783), which pitted the powerful British empire against 13 upstart colonies, wasn’t just fought on the North American continent. The “shot heard round the world” in Concord, Massachusetts, also fired the political ambitions of other European colonial empires, drawing them into the struggle. Many of those ambitions played out in the Caribbean islands—which, far from floating offstage from the American conflict, served as an integral theater of the Revolutionary War.

Ever since Columbus arrived in the Caribbean in 1492, the cluster of islands south of America’s eastern coast had attracted European colonizers—Spanish, British, French and Dutch—eager to cultivate the valuable commodity of cane sugar. In 1776, Britain had several colonies in the Caribbean: Jamaica, Barbados, the Leeward Islands, Grenada and Tobago, St. Vincent and Dominica. The war offered Europe's global powers the opportunity to potentially redraw their colonial maps by scooping up prized Caribbean territories, while knocking the British empire down a peg or two. The region also gave them a base from which to covertly influence the direction of the revolution, with the French and Dutch supplying money, artillery and gunpowder to the Americans by way of their Caribbean territories.

American rebels themselves also conducted war from the Caribbean. Colonial spies flitted from island to island, spreading propaganda and stoking disputes between Britain and its European enemies. By sea, American privateers wreaked havoc on British supply ships, diverting the empire’s military fleet away from the mainland. In fact, these sugar-producing islands became so economically and strategically important that, according to University of Virginia historian Andrew O’Shaughnessy, author of An Empire Divided: The American Revolution and the British Caribbean, the British considered withdrawing from the North American conflict altogether to shore up the defenses of its island territories.

The Caribbean Becomes A Nest for Illicit Trade and Espionage

Early on, the French Caribbean territories of Martinique and Saint-Domingue (present-day Haiti) became crucial to the American war effort. Because Britain banned imports of artillery and powder to the colonies in 1774, the Continental Army was desperate for money and supplies during the war’s first year. The colonies’ only working gunpowder mill could barely sustain the rebels’ firepower needs.

In May 1776, sensing an opportunity to profit, French Foreign Minister Charles Gravier, comte de Vergenne, authorized the covert financing and supplying of American rebels with arms, money and even clothing. Prior to France’s official entrance into the war in 1778, it funneled these goods to American ports via merchant ships from Saint-Domingue and Martinique. It’s estimated the French provided 1.3 billion livres in credit and goods to American rebels.

Martinique also became a base of operations for American spies. One of the most famous, Philadelphia native William Bingham, worked there to cement friendly relations with the French, procure aid (often drawing on French credit arranged for by Benjamin Franklin) and support privateering activity against British ships. The Continental Congress had commissioned more than 2,000 of these freelance ship owners to divert British naval resources away from the mainland. Their strategy: target precious cargo-bearing ships from Britain’s island territories, causing them to need the British fleet’s protection. Thanks to Bingham, harbors in Martinique provided shelter for the booty acquired through privateering activity. And Bingham’s friendly ties with the French governor garnered valuable French maritime protection of goods and arms being ferried to American ports.

The tiny Dutch island of St. Eustatius, which measures only about 12 square miles, also played an outsized role in keeping the American militia armed. Though officially neutral in the conflict, the Dutch saw in the American Revolution an irresistible opportunity to fatten its coffers. In the early 1770s, roughly 2,000 American ships sailed to St. Eustatius annually to trade for sugar. In 1779, however, more than 3,500 American ships, many commissioned on behalf of the rebel government’s Committee of Secret Correspondence, made the journey to the tiny spit of land for stores of ammunition, arms and gunpowder cannily diverted from routes to Africa because of British blockades on European ports.

The illicit gunpowder trade not only amassed enormous profits for Dutch merchants—“in excess of 120 percent,” according to historian Victor Enthoven. Its success at helping keep the American infantry supplied with weapons caused the famous British admiral George Rodney to lament that tiny St. Eustatius “had done England more harm than all the arms of her most potent enemies and alone supported the infamous American rebellion.” After finally intercepting evidence on the illicit trade in 1780, the British officially declared war on the Dutch Republic that year, eventually seizing St. Eustatius.

The Caribbean Becomes a Naval Battleground

The French viewed the American war as an opportunity to regain some of its trade and maritime stature diminished by its stinging losses to the British during the Seven Years’ War (1756-1763). When France officially entered the American Revolution in 1778, it put greater strategic importance on consolidating its Caribbean holdings and picking off British territories than on engaging in conflict on the North American mainland, according to James Pritchard, former professor of history at Queens University, Ontario, in his article “French Strategy and the American Revolution: A Reappraisal.” And the French weren’t alone. In 1779, they lassoed Spain into the war by promising to support Spanish designs on valuable British territories such as Jamaica.

Having to defend its Caribbean possessions dealt a heavy blow to Britain’s plan to concentrate its forces on blockading the North American coast and countering the American insurgency. In December 1778, for instance, the British government siphoned 5,000 troops from New York to help capture the island of St. Lucia, a necessary venture for monitoring enemy activity in that crucial Caribbean rim.

Despite that win, the French, led by admirals such as Charles D’Estaing and François Joseph Paul, comte de Grasse, racked up a string of successes against the British navy. The French menaced British territories like St. Kitts and Barbados and ended up conquering islands such as Dominica (1778), St. Vincent (1799), Grenada (1799) and Tobago (1781).

The French Enable Victory at Yorktown

After the siege on Tobago, with the British playing defense and the added benefit of Spanish forces protecting French territories, Admiral de Grasse sailed unimpeded to find safe harbor in Saint-Domingue. From there, with a fresh injection of 3,000 troops and more than 1.2 million livres in additional funding from Cuban merchants, De Grasse set sail from Saint-Domingue north to the Chesapeake Bay on August 5.

A month later, de Grasse’s victory at Chesapeake Bay blocked delivery of British troop reinforcements desperately needed by Lord Charles Cornwallis and his army at Yorktown, Virginia. The result: the outmanned Cornwallis surrendered to General George Washington on October 17, ending the last major conflict in the war, and securing American independence.

From the outbreak of hostilities in 1775 to the final battles in 1783, the Caribbean became the crucial funnel through which European powers pushed funds and ammunition to American insurgents while jockeying for supremacy. The battling European colonial interests in the so-called New World meant that the economic, political and even cultural fates of mainland and island territories were deeply intertwined. Indeed, America’s struggle for independence would reverberate and catch fire in multiple territories, igniting the political careers of revolutionaries such as Toussaint Louverture (Haiti) and Francisco de Miranda (Venezuela), and sparking debates on the true measure of democracy that smolders in world politics to this day.

HISTORY Vault: The American Revolution

Stream American Revolution documentaries and your favorite HISTORY series, commercial-free.