What is thought to be the last battle flag from the American revolution in private ownership has sold for $422,500 at a November 14 auction in Philadelphia.

The silk battle flag was carried in the 1775-1783 conflict by the Continental Army's Eighth Virginia Regiment, led by the fighting clergyman Colonel Peter Muhlenberg.

The flag’s provenance and rarity combined to achieve a strong price

The flag was consigned by the Muhlenberg family, where it had remained for more than 200 years - an important factor in boosting its attraction to bidders.

Its great rarity, however, was the key selling point, as the auction house's chairman, Samuel M "Beau" Freeman II, explains.

"Revolutionary battle flags are rare and those in private hands are almost unknown or only fragments have survived - this is an extraordinary discovery," he said.

"Muhlenberg is a legendary hero of the Continental Army. This flag… may be the last remaining battle flag in private hands."

The price achieved was despite its salmon-red colour having faded to gold - a testament to the clamour for intact flags from the war of independence.

Peter Muhlenberg famously removed his smock to reveal a military uniform as he read a rousing sermon on January 21, 1776, as the country entered into war.

In a year that has seen George Washington's personal copy of the Acts of Congress sell for $9.8m, the sale is a further reminder of the power of US revolutionary artefacts at auction.

We are currently selling this pre-war signed document by Washington, the Continental Army's commander.