Sarekat Islam or Syarikat Islam ( 'Islamic Association' or 'Islamic Union'; SI) was an Indonesian socio-political organization founded at the beginning of the 20th Century during the Dutch colonial era. Initially, SI served as a cooperative of Muslim Javanese batik traders to compete with the Chinese-Indonesian big traders. From there, SI rapidly evolved into a nationalist political organization that demanded self-governance against the Dutch colonial regime and gained wide popular support. SI was especially active during the 1910s and the early 1920s. By 1916, it claimed 80 branches with a total membership of around 350,000. SI was eventually embroiled in an internal conflict between the Islamic moderates and the radical communist members who urged firmer anti-colonialist and anti-capitalist actions. In 1921, the organization was split and communist members founded a separate entity known as the Sarekat Islam Merah (Red Islamic Association) which was absorbed into the Communist Party of Indonesia (PKI). The split led to the decline of the organization, and the original SI later turned into a political party, the (PSII). PSII was fused into the United Development Party (PPP) in 1973. Today, SI is credited as the first large-scale Indonesian nationalist organization (or mass organization, ormas) and the largest Muslim political organization in the pre-independence era. History Formation The predecessor of Sarekat Islam was Sarekat Dagang Islam (Islamic Trade Association, SDI) which was based on a movement in 1909 in Batavia (today's Jakarta) and 1910 in Buitenzorg (today's Bogor), West Java. This movement was formed by a journalist Tirto Adhi Soerjo who was a member of priyayi (Javanese noble class). Tirto aimed the movement to bring together small-scale pribumi (indigenous) traders and Arab traders unified by the common Islamic religion to advance their economic interests and compete with the Chinese-Indonesian big traders. The movement was also a reaction to the intensified activities of the foreign Christian missionary in Indonesia, which strengthened the position of Islam as a rallying point of native Indonesians' struggle against the foreign encroachment. The movement sparked the interest of Samanhudi, a successful batik trader based in Surakarta. In 1911, Samanhudi founded SDI in the city of Surakarta with the help of Tirto. Expansion On August 12, 1912, SDI was briefly suspended by the colonial government after some conflicts between and Chinese and the occurrence of anti-Chinese riots. After the restriction was lifted, SDI renamed itself to Sarekat Islam on September 19, 1912, in Surabaya.