Ronda Rousey is widely considered one of the most legendary UFC fighters in the game, but it turns out there's something else about her that's just as notable: she has a black ancestor.

Ronda Rousey, Ashley Graham and Hailey Clauson cover Sports Illustrated swimsuit issue.

When TMZ caught up with the Rousey women while out on the town recently, Ronda's mother revealed the fighter's great-grandfather was one of the first black physicians in North America.

Not only that, Dr. Alfred Waddell was so well-known there's even a documentary about him, Before His Time, that chronicles his journey from menial jobs in New York City to Halifax, Canada where he serviced a wide array of patients--even providing lodging for musicians including Cab Calloway when he couldn't get a hotel room. Wow!

Ronda Rousey accidentally predicted her own defeat on The Tonight Show

Check out snippet from the documentary below.