Proclamation of Indonesian Independence

The Proclamation of Indonesian Independence (Indonesian: Proklamasi Kemerdekaan Indonesia, or simply Proklamasi) was read at 10:00 Tokyo Standard Time on Friday, 17 August 1945 in Jakarta. The declaration marked the start of the diplomatic and armed resistance of the Indonesian National Revolution, fighting against the forces of the Netherlands and pro-Dutch civilians, until the latter officially acknowledged Indonesia's independence in 1949. The document was signed by Sukarno and Mohammad Hatta, who were appointed president and vice-president respectively the following day.

The date of the Proclamation of Indonesian Independence was made a public holiday by a government decree issued on 18 June 1946.

In 1918, the Dutch authorities in the Dutch East Indies established a partly-elected People's Council, the Volksraad, which for the first time gave Indonesian nationalists a voice. Meanwhile, Indonesian students studying in the Netherlands formed the Perhimpoenan Indonesia, or Indonesian Association. Among its leaders were future Indonesian vice-president Mohammad Hatta and future prime minister Sutan Sjahrir. In September 1927, Hatta and other members were arrested for inciting resistance to Dutch authority in the East Indies, but thanks to a rousing defense speech by Hatta, they were acquitted. Back in the East Indies, in 1927, nationalist and future Indonesian president Sukarno turned his study club into the Indonesian Nationalist Association, which in May 1928 became the Indonesian National Party (PNI). The party aimed to achieve Indonesian independence through mass-based non-cooperation with the authorities. In October 1928, the representatives at a Youth Congress held in Batavia, the capital, adopted the ideals of one motherland, Indonesia; one nation, the nation of Indonesia; and one language, the Indonesian language. This expression of national unity was a reaction to the older generation, which tended to identify with their region or ethnicity, and subsequently became known as the Youth Pledge.

The PNI grew rapidly, causing concern for the authorities, who arrested Sukarno and seven party leaders in December 1929. They were put on trial for being a threat to public order and in September 1930 received sentences of one to four years – Sukarno received the longest sentence. The PNI dissolved itself in 1931, and in the same year, Sjahrir returned from the Netherlands and established a party called the New PNI which rather than focusing on mass action and being dependent on one leader, aimed to create a group of leaders who could ensure continuity if any were arrested. In 1931, Sukarno was released and joined the small Indonesia Party (Partindo), while in August 1932, Hatta returned from the Netherlands and assumed the leadership of the rival New PNI, which had a more Marxist and revolutionary platform than Partindo. Sukarno was arrested again in August 1933, and was exiled first to Flores, then to Bencoolen, while Hatta and Sjahrir were arrested and exiled to the Boven Digul detention camp in western New Guinea.

The detention of these nationalist figures effectively ended the non-cooperation movement, and in December 1935 the moderate Indonesian National Union and Budi Utomo merged to form the Great Indonesia Party (Parindra), which aimed to work with the Dutch to achieve Indonesian independence. When in 1936, Volksraad member Soetardjo submitted a petition asking for a conference to be held that would lead to Indonesian self-government as part of a Dutch-Indonesian union over a decade, Parindra was lukewarm, resenting the possibility of Soetardjo succeeding where the other nationalist organizations had failed. The petition was passed by a majority of the Volksraad, but rejected by the Dutch in November 1938. In May 1937, Parindra, the Indonesian People's Movement (Gerindo), was established by younger Marxists including Amir Sjarifuddin, another future prime minister, to campaign for the formation of an Indonesian parliament in cooperation with the Dutch, which was the same aim of the Indonesian Political Federation (GAPI), formed two years later from a merger of almost all the nationalist organizations. However, the outbreak of the Second World War resulted in the occupation of the Netherlands, and the Dutch government in exile was in no position to respond to GAPI's request for a Dutch-Indonesian union and an elected legislature, although Dutch Queen Wilhelmina made a speech in London in May 1941 promising unspecified changes to the relationship with the East Indies after the war.

On 23 January 1942, three years before the 1945 proclamation, an independence activist Nani Wartabone declared "Indonesian independence" after he and his people won in a revolt in Gorontalo against the Dutch who were afraid of Japanese invasion of Celebes. He was later imprisoned by the Japanese after they had invaded the area.

With the outbreak of the war in the Far East, and the initial successes of Japan, in early 1942, the Dutch authorities gave Amir Sjarifuddin money to establish an underground resistance movement and sent Hatta and Sjahrir back to Java. In January 1942, the Japanese invaded the Dutch East Indies, and rapidly overran the archipelago. The Dutch surrendered on 8 March. The Japanese banned the use of the Dutch language as well as the Indonesian flag and anthem, and the Japanese calendar was imposed. The archipelago was administered as three separate regions: Sumatra by the Twenty-Fifth Army, Java and Madura by the Sixteenth Army and Kalimantan and the resource-rich eastern islands by the Imperial Japanese Navy. As the area controlled by the Navy was the source of essential supplies, including food, to the other areas, rear-admiral Tadashi Maeda was appointed to the liaison office of the naval attaché in Batavia to expedite deliveries and to ensure the maintenance of good relations with the Army.

In April 1943, the Japanese established the Triple-A mass movement. Its name was taken from the Japanese propaganda slogan portraying Japan as the leader, protector and light of Asia. However it failed to gain support as no significant Indonesian nationalists were involved, and the propaganda was too heavy-handed. The Japanese then decided that it would be more effective to use pre-war nationalists to mobilize the population in support of their war aims. In July, the 25th Army freed Sukarno from exile in Sumatra, and he joined Hatta and Sjahrir in Jakarta, as Batavia had been renamed. They agreed that Sjahrir would work underground, while Sukarno and Hatta would cooperate with the Japanese, still with the ultimate goal of Indonesian independence. The two men urged the Japanese to establish a popular political organization that they would lead, and this came about in March 1943 with the formation of Putera, the Centre of People's Power. Although it was controlled by the Japanese, it was led by Sukarno, Hatta, Hajar Dewantara and pre-war Islamic figure Mas Mansoer. Like the Triple A, it achieved very little.