A famous portrait of the first president of the United States, George Washington, as commander of the Continental Army during the Revolutionary War, has sold for $5.5 million. The record-breaking price is partly because of the friendship between the painting's subject, its artist and its first owner.

In the portrait of the country's first commander in chief, George Washington is seen in his army uniform, standing casually under a darkened sky, his arm resting on a cannon barrel.

The Revolutionary War portrait artist Charles Wilson Peale painted General Washington in 1779, when the outcome of the war was still uncertain.

Mr. Peale also served as a soldier under General Washington and it was during wartime that he met his future patron, French General Chevalier Francois-Jean de Chastellux.

Major-General Chastellux led French forces fighting alongside the Americans in the war. He became friends with many leading figures of the American Revolution, including Benjamin Franklin, Thomas Jefferson and George Washington.

Mr. Chastellux acquired Mr. Peale's portrait of George Washington near the end of the war and it had been kept in his family for more than 200 years.

The anonymous winning bidder at Christie's auction house in New York exceeded the portrait's estimated price by more than $1 million.

Auctioneer: ?Fair warning now, it's selling to this telephone with Eric, at $5.5 million, all done. Eric, you're the bidder at $5.5 million, all done.?

With taxes and auction house fees, an American private collector paid more than $6 million dollars for the work, setting a new record price for an American portrait.