Wikipedia
Sōhyō
The , often abbreviated to , was a left-leaning union confederation. Founded in 1950, it was the largest in Japan.
A large portion of Sōhyō merged with the more conservative Japanese Confederation of Labor (Domei) and other unions to form Rengo in 1987. Rengo was formally launched in 1989. Some elements of Sōhyō also joined the National Trade Union Council (Zenrokyo).