In the United States many peoples first exposure to Brazilian Jiu was in 1993 during the first UFC. The 170 lb. Royce Gracie defeated larger and more athletic opponents by forcing them to tap by way of chokes and arm leverages. Through his use of technical ground work and finesse, it was now clear that technique was far superior to athleticism and strength. Brazilian Jiu Jitsu, also know as BJJ, or Gracie Jiu Jitsu can literally be translated into the words "gentle art".
Helio Gracie, not the strongest or most athletic individual was the father of Royce. Helio spent his life refining the technique and often said that the martial arts he taught were to the give the weaker man a fighting chance over the bigger stronger opponent. He worked diligently to find out what what worked and what didn't. This concept of keeping what worked and what didn't and also using technique over strength is what makes Sambo and Brazilian Jiu Jitsu alike. This is why these two styles are the main influences over the Jungles submission grappling techniques.