"William Brown"

HMS Queen Charlotte bearing the flag of Vice Admiral Keith,
Anchored in Cadiz Bay

William Brown (birth name unknown) was a Black woman who joined the Royal Navy as a man. One story is that she was born in Edinburgh, joined in 1804 and served at least until at least 1816, even after Brown's birth sex was discovered in 1815. More probably she was from Grenada and only served for a month before discovery. The Annual Register of September 1815 reported:

“Amongst the crew of the Queen Charlotte, 110 guns, recently paid off, is now discovered, was a female African, who served as a seaman in the Royal Navy for upwards of eleven years, several of which she has been rated able on the books of the above ship by the name of William Brown, and has served for some time as the captain of the fore-top, highly to the satisfaction of the officers. She is a smart well formed-figure, about five feet four inches in height, possessed of considerable strength and great activity; her features are rather handsome for a black, and she appears to be about 26 years of age. Her share of prize money is said to be considerable, respecting which she has been several times within the last few days at Somerset-place. In her manner she exhibits all the traits of a British tar, and takes her grog with her late mess-mates with the greatest gaiety. She says she is a married woman; and went to sea in consequence of a quarrel with her husband, who, it is said, has entered a caveat against her receiving her prize money. She declares her intention of again entering the service as a volunteer."

This is not borne out by the Queen Charlotte's muster lists. When the crew were paid off in August 1815, the only William Brown on the list was a 32 year old Scot who had transferred from the Cumberland a month earlier. The list does show though that a 21-year old William Brown had joined the crew from Grenada on May 23, 1815 as a 'landsman' (the least experienced rating), and was discharged a month later for 'being a female'. There is no record of any William Brown being appointed Captain of the fore-top for the Queen Charlotte.
However, this still makes Brown the first known black, biologically female individual to serve in the Royal Navy.