Text 2 The draft was prepared only a few hours earlier, on the night of 16 August, by Sukarno, Hatta, and Soebardjo, at Rear-Admiral Maeda (Minoru) Tadashi's house, Miyako-Doori 1, Jakarta (now the "Museum of the Declaration of Independence", JL. Imam Bonjol I, Jakarta). The original Indonesian Declaration of Independence was typed by Sayuti MelikMaeda himself was sleeping in his room upstairs. He was agreeable to the idea of Indonesia's independence, and had lent his house for the drafting of the declaration. Marshal Terauchi, the highest-ranking Japanese leader in South East Asia and son of Prime Minister Terauchi Masatake, was however against Indonesia's independence, scheduled for 24 August. While the formal preparation of the declaration, and the official independence itself for that matter, had been carefully planned a few months earlier, 19 the actual declaration date was brought forward almost inadvertently as a consequence of the Japanese 18unconditional surrender to the Allies on 15 August following the Nagasaki atomic bombing. The historic event was triggered by a plot, led by a few more radical youth activists such as Adam Malik and Chairul Saleh, that put pressure on Sukarno and Hatta to proclaim independence immediately. The declaration was to be signed by the 27 members of the Preparatory Committee for Indonesian Independence (PPKI) symbolically representing the new nation's diversity. Sumber: https://en.wikipedia.org What does this mean ‘ unconditional surrender… ’?

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Text 2

The draft was prepared only a few hours earlier, on the night of 16 August, by Sukarno, Hatta, and Soebardjo, at Rear-Admiral Maeda (Minoru) Tadashi's house, Miyako-Doori 1, Jakarta (now the "Museum of the Declaration of Independence", JL. Imam Bonjol I, Jakarta). The original Indonesian Declaration of Independence was typed by Sayuti MelikMaeda himself was sleeping in his room upstairs. He was agreeable to the idea of Indonesia's independence, and had lent his house for the drafting of the declaration. Marshal Terauchi, the highest-ranking Japanese leader in South East Asia and son of Prime Minister Terauchi Masatake, was however against Indonesia's independence, scheduled for 24 August.

While the formal preparation of the declaration, and the official independence itself for that matter, had been carefully planned a few months earlier, 19 the actual declaration date was brought forward almost inadvertently as a consequence of the Japanese 18unconditional surrender to the Allies on 15 August following the Nagasaki atomic bombing. The historic event was triggered by a plot, led by a few more radical youth activists such as Adam Malik and Chairul Saleh, that put pressure on Sukarno and Hatta to proclaim independence immediately. The declaration was to be signed by the 27 members of the Preparatory Committee for Indonesian Independence (PPKI) symbolically representing the new nation's diversity.

Sumber: https://en.wikipedia.org

What does this mean ‘unconditional surrender…’?