Underworld exist, sometimes they play an important role in human history, but as we know history is written by who. We know why they never go down history.
He is 王芗斋, a martial art expert in the main land china, and is famous for inventing the matial art 意拳 or people in the field would like to call it 大成拳.
Most many martial artist in china are in some way or another involve in the underworld(黑帮) of China, but not him, he exist for the purpose of perfecting martial art.
When he was a kid, his parent send him for martial art class in hope of strenghtening this weak body. He falls sick quite often and the docter said he would 夭折.
Soon he proved them wrong, not only did he survived pass his prime age but also manage to become the greatest martial master of all time. He was never bittenin martial arts in his life time.
At his old age, he call himself 矛盾老人 which means contradictory old man literally.
He also invented the art of 站桩 for healing and wholeness of body, sort of like Yoga. I use to practice the art some times ago, this post stands to remind me to pickup again.
other article to read about martial art and China underworld -
Update: Someone has an answer on the formation of 洪門與青幫 here. How true is it?