Kano Ryu Jujutsu (fixed it)

Judo is just a name created at 1925 to identify Kano Ryu Ju-jutsu style. Of course BJJ adopted wrestling and sambo, however the root of BJJ is the same Ne-Waza performed by Kodokan at very begining of JoDu history.

It was never called Kano Ryu JJ. He trained in JJ but called his system judo.

When Maeda left Japan, Judo was also known as Kano Jiu-Jitsu and, even more generically, simply as Jiu-Jitsu. Teachers of both arts didn't try too hard to make the distinction clear. Tsunejiro Tomita himself co-authored a book called Judo: The Modern School of Jiu-Jitsu in around 1906. Outside Japan, however, this distinction wasn't even hinted.

The Japanese government itself did not officially mandate until 1925 that the correct name for the martial art taught in the Japanese public schools should be "judo" rather than "jujutsu". In Brazil, the art is still called "Jiu-Jitsu". When the Gracies went to the United States to spread their art, the system became known as "Brazilian Jiu-Jitsu" and "Gracie Jiu-Jitsu.

If you know the meaning of "DO", you know the difference between Ju-DO and Ju-Jutso. If you know the meaning of DO you also know the difference between Ken-DO and Ken-Jutso, and Aiki-DO and Aiki-Ju-jutso.

BJJ is a grappling art derived from Judo which perfects the most effective ground techniques. The art began with Mitsuyo Maeda, a Japanese expert judoka and member of the Kodokan. Maeda was one of five of the Kodokan's top groundwork experts that Judo's founder Kano Jigoro sent overseas to spread his art to the world.

Maeda left Japan in 1904 and visited a number of countries giving demonstrations and accepting challenges from wrestlers, boxers, savate fighters and various other martial artists before eventually arriving in Brazil on November 14, 1914.

sambo is also derived from kano jiu jitsu.

NO Maeda did NOT study ANY Koryu Jujutsu, he did spend a bit of time in Sumo prior to coming to Kano and the Kodokan, but there is no historical information or evidence that he spent any time in ANY Koryu Jujutsu. Maeda was a Judoka plain and simple.