Mitsuyo Maeda was born in 1878, and joined the Kodokan Judo Institute in 1895, having already practiced sumo and Tenjin Shinyo jujitsu. Maeda's instructor was Tsunejiro Tomita, the very first student at the Kodokan.
Maeda eventually became a professional wrestler, one of countless underappreciated ties between MMA and pro wrestling, performing, competing, and demonstrating in the USA, Europe, Cuba, Mexico, Central America, and then Brazil, where he settled and eventually was buried.
Maeda taught members of Gastão Gracie's family. The curriculum is unknown, but likely incorporated judo (which in turn drew from jiu-jitsu), catch as catch can wrestling, and methods Maeda developed on his own. That teaching spawned a martial arts practice in Brazil referred to there as jiu-jitsu, with a strong emphasis on groundwork over throwing,
The practice was refined over generations through competitions with various rule sets including none (Ryan Gracie famously bit the ear off of a Carlson Gracie student named Tico, after the latter attempted an eye gouge; the mat was a brick patio).
The result is an extraordinary martial art, the efficacy of which speaks for itself, to all but the befuddled. It rests on the use of setups and leverage, developed with extraordinary rigor through practice that centers on trained, active resistance. It is such a profound exhibition of human performance that SBG founder Matt Thornton argues, "There is no such thing as Canadian geometry for the same reason there is no such thing as Tibetan physics, or Malaysian oncology. Things that are testable, falsifiable, and empirically true, are by their very nature, unbound by culture, geography, or time."
Mastery of this manifestation of jiu-jitsu, as represented by a black belt, takes about a decade of hard, hard work, and confers all the fighting ability that the vast majority of martial arts claim to possess, but manifestly do not.