Champion Carnival
From 1959 to 1972, the Japan Pro Wrestling Alliance (JWA), run by Rikidōzan, held a tournament called World League (also known as the "World Big League"), which featured both Japanese and foreign professional wrestlers. Rikidōzan himself dominated the annual tournament early on, however, after his death in 1963, the tournament was won six times by Giant Baba and once by Antonio Inoki. JWA folded shortly after both Baba and Inoki left the promotion to create All Japan Pro Wrestling (AJPW) and New Japan Pro-Wrestling (NJPW), respectively. Both men took the concept of World League with them to their new promotions, with Baba creating the "Champion Carnival" in 1973 and Inoki creating the World League in 1974, later renaming it G1 Climax.
International Wrestling Association of Japan
The International Wrestling Association of Japan, more commonly known as IWA Japan, was a Japanese professional wrestling promotion operating from 1994 to 1996 and again from 2011 onwards. It was formed by Victor Quiñones as a successor to the W*ING promotion, which was folding at the time as a rival to Frontier Martial-Arts Wrestling (FMW), the pioneer of deathmatch wrestling in Japan and the only deathmatch promotion in Japan at the time. Most of the wrestlers jumped ship to Quiñones' new IWA Japan group. He found a sponsor in Tatsukuni "Kinroku" Asano, a business man who owned several restaurants in Tokyo and had bought and run several wrestling shows prior to IWA Japan.