In 1925, Comintern representative Sergei Gusev ordered the majority Foster faction to surrender control to Ruthenberg's faction; Foster complied.
Sirola was a representative of the Communist International to the US Communist Party from 1925 to 1927, replacing Sergei Gusev.
Sergei Rachmaninoff | Sergei Prokofiev | Sergei Eisenstein | Sergei Parajanov | Sergei Diaghilev | Sergei Witte | Sergei Ivanov | Sergei Ivanovich Osipov | Sergei Bondarchuk | Sergei Bagapsh | Ivan Sergei | Sergei Yefimovich Zakharov | Sergei Polusmiak | Sergei Osipov | Gusev | Grand Duke Sergei Alexandrovich of Russia | Sergei Zimin | Sergei Ordzhonikidze | Sergei Kurzanov | Sergei Babayan | Sergei Yursky | Sergei Tretyakov | Sergei Sychyov | Sergei Stadler | Sergei Skripka | Sergei Pavlovich Baltacha | Sergei Pavlenko | Sergei Lyapunov | Sergei Gusev | Sergei Gukov |