The Origin of Wing Chun
As with many legends it is impossible to confirm or clarify the story of Wing Chun's creation. This is one of the most accepted versions:
Yim Wing Chun had secretly trained in Kung Fu with her father since early childhood. This was during the reign of Emperor Jiaqing (1796-1820) when Kung Fu masters who opposed the Qing Dynasty were hunted down and murdered.
As a teenager, Yim Wing Chun caught the eye of a local warlord. She managed to rebuff his advances until he made a startling offer: he would rescind his marriage proposal if she could beat him in a fight. Although he outweighed her by 100 pounds, she agreed. The warlord gave her until the following spring to prepare for the fight and to become his bride.
Ng Mui, an older woman, and one of the Shaolin Five Elders who had managed to escape the burning of their temple, had been using her time in hiding to synthesize a new fighting system out of the Snake and Crane styles of Shaolin Kung Fu. Her goal was to invent a style a woman or other fighter who did not have the advantage of size and strength could use. She began training Yim Wing Chung in the most essential elements of the new style.
By spring, with her entire village watching, Yim Wing Chun demonstrated a type of Kung Fu that had never been seen before. She used the warlord's mass and strength against him, flowing around his attempts to strike or grab her. She threw her entire bodyweight into specific targets, breaking his balance and leaving him vulnerable to repeated strikes. When the warlord crumpled unconscious at Wing Chun's feet, a roar went up from the crowd.
After marrying the man of her choice, she and her husband established a secret school to teach the new style. After moving to Zhaoqing in Guangdong Province, they began teaching again, naming the style Wing Chun Kung Fu.
Source: Wing Chun Concepts