Sumiyoshi-kai is a prominent yakuza organization based in Japan, primarily operating in the Osaka region. Established in the early 20th century, it is known for its traditional values and strong ties to local communities. The group engages in various activities, including legitimate businesses and illegal enterprises. The Sumiyoshi-kai is recognized as one of the largest yakuza groups in Japan, with a hierarchical structure and a code of conduct that emphasizes loyalty and respect. It has been involved in conflicts with other yakuza factions, particularly during the yakuza wars of the late 20th century, which shaped its current influence and operations.