The Indonesian independence movement began in May 1908, which is commemorated as the "Day of National Awakening" (). Indonesian nationalism and movements supporting independence from Dutch colonialism, such as Budi Utomo, the Indonesian National Party (PNI), Sarekat Islam and the Indonesian Communist Party (PKI), grew rapidly in the first half of the 20th century. Budi Utomo, Sarekat Islam and others pursued strategies of co-operation by joining the Dutch initiated "Volksraad" ("People's Council") in the hope that Indonesia would be granted self-rule. Others chose a non-cooperative strategy demanding the freedom of self-government from the Dutch East Indies colony. The most notable of these leaders were Sukarno and Mohammad Hatta, two students and nationalist leaders who had benefited from the educational reforms of the Dutch Ethical Policy.