Ryohei Uchida [1] founded the Kokuryu-kai, or Amur River Society in 1901. The Japanese characters for Kokuryu-kai had a double meaning and was taken to be "Black Dragon." The exotic version of the name caught on with Western journalists. Uchida was a follower of Mitsuru Toyama, founder of the Genyosha (Dark Ocean Society). Toyama remained an advisor to Uchida and the Black Dragons until his death in 1944. Uchida's Black Dragons took over the roles and traditions set by Genyosha. From its founding, until 1945, Black Dragon provided the Japanese Army and government with espionage and subversion services [2] worldwide, but most especially in China. Uchida was succeeded [3] by Kuzuo Yoshihisa in 1937. Uchida was also President [4] of The Japan Production Party. Genyosha, or Dark Ocean Society was also known as Black Ocean Society in some translations.

[1] David E. Kaplan and Alec Dubro, Yakuza: The Explosive Account of Japan's Criminal Underworld, page 36.

[2] Richard Deacon, Kempei Tai: A History of the Japanese Secret Service, pages 41, 44, 47, 55, 71, 83, 87, 132, 137-139, 143.

[3] Richard Storry, The Double Patriots: A Study in Japanese Nationalism, page 312.

[4] Storry, page 309.