The rengo was formed by an alliance of the Shotozumi-kai, the Nishidon-kai, the Karatsa-kai, and the Shigeda-kai, with a majority of the manpower and resources coming from the Yamaguchi-gumi boryokudan. Around 2021, most of the Watada-rengou boryokudan forced out or absorbed the smaller, non-allied Yakuza gangs. The Watada-rengou is believed to be heavily tied to the Great Eastern Dragon Ryumyo, in an alliance formed around 2027 -- which led to the Watada becoming the most powerful yakuza clan in Japan.
The Watada-rengo is described as part of the "Old School" or "Traditionalist" part of the Yakuza. It is the largest and most powerful of the Yakuza groups with a worldwide reach.
The oyabun of the Watada was Akira Watada until his death in 2070, leading to a quarrel of succession. Akira's nephew Hitori Hanzo was kumicho, and then oyabun briefly before being assassinated in 2070, but managed (as war boss) to crush the Shotozumi Uprising in Japan. Maasaki Watada was named as Hanzo’s replacement.
Nation-states with syndicate members of the Watada-rengo;
Individual boryokudan in the Watada-rengou;