Kakumaru-ha evolved into its current form after a series of schisms. In 1959, Kuroda Kan'ichi was expelled from the RCL in the wake of a scandal in which he tried to sell compromising information about the JCP to the Tokyo Metropolitan Police Department (MPD). Therefore, Kuroda, along with his right-hand man Nobuyoshi Honda, founded their own version of the RCL, with the appellation "National Committee" added to the name, and took many of their followers with them to create the RCL-NC. In 1960, a youth branch of the RCL-NC was established for Zengakuren student activists as the Marxist Student League (MSL), abbreviated Marugakudō in Japanese.
