I believe a Judoka master (Otávio Mitsuyo Maeda) travelled to Brazil instead and taught the late Carlson Gracie. Carlson in turn showed Helio and he took it to the next level...JJ started in Japan as a method to kill. It was dying because of that very fact and a gentleman invented Judo as a non-killing JJ. This saved JJ as people could prepare using non-lethal training.
I forget the Gracie that studied both in Japan, but he brought it back to Brazil. Most JJ is the same with minor differences between Countries and dojo's.
Brazilian JJ, for instance, is ground based
Brazilian Jiu-Jitsu (BJJ) was developed after Mitsuyo Maeda brought judo to Brazil in 1914. At the time, judo was still often commonly referred to as "Jiu-Jitsu", which explains why this derivative of judo is called Brazilian Jiu-Jitsu rather than Brazilian Judo. BJJ dominated the first large modern mixed martial arts competitions, causing the emerging field to adopt many of its practices. The stand-up techniques in Gracie Jiu Jitsu are largely from Japanese Jujutsu (knife defence, gun defence, throws, blocking, striking etc).
You're my hero.I was in the crowd of UFC 1, infact I convinced Dana to start the promotion when he bought Chuck over from K-1. I said let me show you, Graces Ninjitsu is the most effective martial art ever. So we put this thing together, i'm thankful it worked out.