Today’s Japanese Communist Party (JCP) may hold only a small fraction of the seats in Japan’s parliament, the National Diet. However, it exudes a presence as an outspoken critic and watchdog of the ruling regime that is disproportionate to its size.

In 2019, for example, the JCP newspaper Akahata reported that the late conservative prime minister Abe Shinzō had privately invited numerous political supporters to the state-funded “cherry blossom viewing event” for honoring meritorious achievements. The following year, it revealed that Abe’s successor, Suga Yoshihide, had blocked the appointment of six scholars to the Science Council of Japan due to their political views. Both revelations triggered widespread public outrage against corruption and abuse of power by the ruling Liberal Democratic Party (LDP) cabinet.

From its establishment by the Communist International one hundred years ago, whose leaders hoped that it would lead a proletarian revolution in Japan, the JCP has undergone multiple transformations. It has survived into the post–Cold War period as a small but significant countervailing force against the excesses of the country’s political powerholders. As Japan’s oldest political party, it is a unique player on the domestic scene, with few if any true counterparts in the developed capitalist world.