With growing popular support and a membership of about three million by 1965, the PKI was the strongest communist party outside China and the republics of the Soviet Union. The party had a firm base in mass organizations such as the Central All-Indonesian Workers Organization (Sentral Organisasi Buruh Seluruh Indonesia), People's Youth (Pemuda Rakjat), the Indonesian Women's Movement (Gerakan Wanita Indonesia), the Peasants Front of Indonesia (Barisan Tani Indonesia), the Institute of People's Culture (Lembaga Kebudajaan Rakjat) and the Association of Indonesian Scholars (Himpunan Sardjana Indonesia). At its peak, the total membership of the party and its front organizations was claimed to be one-fifth of the Indonesian population.