According to Wikipedia, Japanese karate was first practiced in 1936:
Funakoshi had trained in two of the popular branches of Okinawan karate of the time, Shorin-ryū and Shōrei-ryū. In Japan he was influenced by kendo, incorporating some ideas about distancing and timing into his style. He always referred to what he taught as simply karate, but in 1936 he built a dōjō in Tokyo and the style he left behind is usually called Shotokan after this dōjō.
South Korean tae kwon do was first practiced in 1966:
As a response to this, along with political disagreements about teaching Taekwondo in North Korea and unifying the whole Korean Peninsula, Choi broke with the (South Korea) KTA in 1966, in order to establish the International Taekwon-Do Federation (ITF)— a separate governing body devoted to institutionalizing his Chan Hon-style of Taekwondo in Canada.
And Chinese kung fu was first practiced in 1979:
In 1979, the State Commission for Physical Culture and Sports created a special task force to revaluate the teaching and practice of Wushu.
Is the invention of South Korean tae kwon do based on Japanese karate? And then what about the invention of Chinese kung fu? Is kung fu based on either karate or tae kwon do?
I have tried to do some research online, but have not been able to find an answer.