An American Revolutionary War hero credited with saving the life of future US President George Washington has been revealed to be a woman or possibly intersex.
Casimir Pulaski was born in Poland, and was already an accomplished soldier before joining the American colonies' battle for independence, after a chance meeting with Benjamin Franklin in Paris.
In 1777's the Battle of Brandywine, Pulaski's forces held off the advancing Brits, allowing Washington to escape to fight another day. Pulaski was shot dead during a battle two years later in Savannah, Georgia.
The ultimate resting place of the body has long been debated, with conflicting reports he was either buried at sea or in Monterey Square in Savannah.
The remains were exhumed in 1996, and forensic anthropologists Charles Merbs and Karen Burns immediately noticed something wasn't right.
"Dr Burns said to me before I went in, 'go in and don't come out screaming'," Arizona State University's Merbs said. "She said study it very carefully and thoroughly and then let's sit down and discuss it.
"I went in and immediately saw what she was talking about. The skeleton is about as female as can be."
Clues included the shape of the pelvis, and the skeleton's stature and shape.
But according to the historical record Pulaski was a man, and DNA tests with the technology available at the time were inconclusive.
Suspicion remained however, as the skeleton showed other clues it belonged to Pulaski. There were fractures in the right hand which matched an injury Pulaski was known to have received; a bone defect below his left eye which matched a black smudge in the only known contemporary portrait of the war hero; and evidence the skeleton's owner spent a lot of time on horseback swinging a sword, as cavalry did in the 1700s.
"Everything matched, except for the sex," said Merbs.
Three young researchers at Arizona State University recently decided to take another look, hoping DNA technology could now prove one way or the other if it was Pulaski. The DNA collected in the 1990s was re-tested, and it confirmed the bones did indeed belong to Pulaski.
"I don't think, at any time in his life, did he think he was a woman" or intersex, Merbs said.
"I think he just thought he was a man, and something was wrong. He had some kind of defect or something. Back in those days they just didn't know."
There were clues at the time, the researchers say - unlike most of his colleagues, Pulaski had no interest in women or drinking alcohol.
Every year since 1937, New York's Polish community has held a parade in Pulaski's honour. Organiser Richard Zawisny told NBC News although he's a "little shocked", the revelation won't change anything.
"In this day and age I don't think it will matter to most people."
It's estimated around 1.7 percent of babies are born some degree of intersex.
More details about the finding will be aired in a documentary, America's Hidden Stories: The General Was Female, set for broadcast in the US on the Smithsonian Channel on Tuesday (NZ time).