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Americans celebrate July 4 as their independence day, a moment of patriotic pride and exuberance. On this day (more or less) in 1776, an assembly of unruly colonials in Philadelphia adopted the Declaration of Independence, stating emphatically "That these United Colonies are, and of right ought to be, free and independent States ... absolved from all allegiance to the British Crown."

But as popular historian Larrie Ferreiro argues in a recent book, the document should also be considered a "Declaration That We Depend on France (and Spain, Too)." Ferreiro's "Brothers at Arms: American Independence and the Men of France and Spain Who Saved It" — a finalist for this year's Pulitzer Prize in history — places the American Revolution in its proper international context, showing how the fitful efforts of America's Founding Fathers might have come to nothing without the vital support of foreign powers.

Ferreiro spoke to Today's WorldView earlier this year. Below is an edited version of our conversation.

A copy of the U.S. Declaration of Independence at the West Sussex Record Office in Chichester, Britain, on April 27. (Hannah McKay/Reuters)

Explain to us how the Declaration of Independence was a cry for outside help.

We typically look at the Declaration of Independence as a document written to King George III by the American people, stating why we wanted to become an independent nation. That's what we tell each other when we celebrate the Fourth of July.

But when you look at what happened in 1776, it was clear George III had already got the memo that the Americans wanted to be independent. And when you look at the writing of the Founding Fathers, they make it very clear that they knew they could not fight Britain by themselves. They knew that the only countries that had the motivation and the military and naval capabilities to defeat Britain were France and Spain. And the only way they could join on the Americans' side was if they knew this was not simply a battle of colonists with their mother country to get a better deal. They only would come to our aid if they saw that we were fighting as a sovereign, independent nation against a common adversary.

The Declaration was specifically written for that purpose, and both John Adams and Thomas Jefferson said this — they were quite clear in their writings. Thomas Jefferson took those ideas and made a document for the ages, a truly enlightened document that read out many of the ideas of the time on what constitutes the rights of the state and the people. But at the core it was a cry for help. The first considered action by Congress after the Declaration was approved was to put it on a ship so it could reach the courts of France and Spain.

What did the French and Spanish support look like once they entered the war?

There were three factors: The first was arms and money. Ninety percent of all firearms the Americans used — as well as the equivalent of $30 billion in aid — came from overseas, primarily from France and Spain. It was what allowed us to survive in the beginning and middle of the war, and continue the war through to its conclusion.

The second was the volunteers and then soldiers under French and Spanish command who came to fight. Many of these foreign volunteers helped train the Continental Army to fight the British on their terms. You couldn't win a war with snipers firing from behind trees. And at Yorktown, of course, it was a combination of French guns and troops along with the with Americans that forced [Gen. Charles] Cornwallis to surrender.

The third and most important aspect was naval power. Britain was a naval power, and it was only on the sea where it could really be defeated. The overarching story of why Britain came to the peace table was because they were fighting five separate nations on the oceans all around the world by the time of Yorktown. Their navy was overwhelmed. They could not continue to resupply and fight on such a vast canvas. Ships and troops were absorbed in Europe and India and, of course, the Caribbean. What a lot of people keep forgetting was that the real prize was the Caribbean. The sugar colonies were where the money was minted.

People move between opening ceremonies for the Museum of the American Revolution in Philadelphia on April 19. (Matt Rourke/Associated Press)

In other words, geopolitics are often underappreciated in the story of American independence.

That was the real story: We were in the middle of this coalition of nations which were together fighting a common adversary. When the American Revolution began in 1775, it was really a confluence that brought all these nations together. France and Spain started by covertly giving arms to the Americans  — they knew if they were able to keep the British occupied in Americas, there was less chance of the Brits making mischief in Europe. All of this happened in a global context, not just in North America, but in the Caribbean, Gibraltar and Minorca and in India.

The Marquis de Lafayette is perhaps the most well-known foreign ally of the Americans. Were there other important personalities?

Lafayette was an important figure both at the time and subsequently, but he was not the most important figure — not by a long shot. The idea that Lafayette was a vital bridge between America and Europe wasn't really cemented until 50 years later, when he made a tour of all 24 states in the U.S that really cemented his reputation as the centerpiece.

At the top of the list must come the Comte of Vergennes, the foreign minister of France. He made all the major decisions about the alliance both with America as well as the operations across the world with Spain. Some others include his counterpart, the Spanish minister Conde de Floridablanca; Bernardo de Galvez, a pugnacious soldier who carried out lightning raids that captured many British outposts and brought Pensacola under Spanish rule; the Comte de Grasse, the French admiral who managed to keep the British from reinforcing Corwallis; the Comte de Rochambeau [commander of all the French forces in the American Revolution], Washington’s counterpart, and spiritual and intellectual equal.

Washington firing the first American gun at Yorktown. (Colonial Williamsburg)

Does the fact that U.S. independence was so contingent on European empires cloud the story of American freedom?

We did not begin the process of independence for Enlightenment reasons so much as the hope to conduct our business the way wanted to. Most of our prosperity was coming from our agricultural trade with Europe and the Caribbean, and it was the restrictions on this trade that were becoming burdensome to Americans. We didn’t get into this fight for some noble concept of liberty and justice — we wanted to be able to pursue our economic liberty in a way we sought fit without these onerous restrictions the British put upon us.

Why does this larger international story feel so absent in the American historical imagination?

This story of America bootstrapping its way to independence really began in the middle of the 1800s, the era of Manifest Destiny. We were trying to push west, and we had this idea of American exceptionalism and superiority to the Europeans we were descended from. In that story you needed a really strong central figure — that was George Washington and his generals.

But having help from the people we were saying we were superior to didn't fit the narrative. That perpetuated itself into the 20th century. In recent decades, there has been a broader view, pulling in the role played by enslaved Africans, Native Americans and other groups. There's a growing awareness that the Revolution was not as neat and tidy a story as we were led to believe.

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