One of America’s most revered military commanders, Casimir Pulaski, turns out to have been either a woman or intersex, according medical experts and quoted in a new documentary.

The Polish-born general, who has been credited with saving the life of George Washington during the 1775-83 Revolutionary War against Britain, is known as the “Father of the American Cavalry.”

He went to the US voluntarily to fight, and was known for his extraordinary bravery in battle as well as for being a very private person, difficult to deal with and having no interest in women or drinking.

Today, a town in New York bears his name, as does a freeway and many public buildings.

Researchers first made the discovery about Pulaski’s sex 20 years ago, when a monument to the general in Savannah, Georgia, was dismantled and Pulaski’s bones were exhumed.

Charles Merbs, then a forensic anthropologist at Arizona State University, studied the bones together with Karen Burns, a physical anthropologist.

“Dr Burns said to me before I went in, ‘Go in and don’t come out screaming,'” he told the university in an article published this week.

“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.”

At that time, despite tracking down the bones of a female relative of Pulaski, researchers did not have the DNA techniques that could definitively prove the bones in the monument belonged to Pulaski.

However last year, three researchers at ASU took up the case again – and were able to match mitochondrial DNA in both Pulaski and his grand niece.