The Taiwanese Aboriginal tribes who were previously allied with the Dutch against the Chinese during the Guo Huaiyi Rebellion in 1652 turned against the Dutch during the Siege of Fort Zeelandia and defected to Koxinga's Chinese forces. The Aboriginals (Formosans) of Sincan defected to Koxinga after he offered them amnesty, and proceeded to work for the Chinese, beheading Dutch people. The frontier aboriginals in the mountains and plains also surrendered and defected to the Chinese on 17 May 1661, celebrating their freedom from compulsory education under Dutch rule by hunting down Dutch people and beheading them, and by destroying their Protestant school textbooks. On 1 February 1662, the Dutch Governor of Formosa, Frederick Coyett, surrendered Fort Zeelandia to Koxinga. According to Frederick Coyett's own self-justifying account written after the siege, Koxinga's life was saved at the end of the siege by a certain Hans Jurgen Radis of Stockaert, a Dutch defector who strongly advised him against visiting the ramparts of the fort after he had taken it, which Radis knew would be blown up by the retreating Dutch forces. This claim of a Dutch defector only appears in Coyett's account and Chinese records make no mention of any defector. In the peace treaty, Koxinga was styled "Lord Teibingh Tsiante Teysiancon Koxin" (大明招討大將軍國姓). This effectively ended 38 years of Dutch rule on Taiwan. Koxinga then devoted himself to transforming Taiwan into a military base for loyalists who wanted to restore the Ming dynasty.