 The key factors of their protest were because all Sultans of Malay states would lose their power as the ruler of their respectable states, and the way Sir Harold MacMichael threatened the Sultans for their signatures.Sultan Ibrahim of Johor himself was encouraged by MacMichael to sign on the treaty, sparking anger among Malays, claiming that signing the Malayan Union treaty violated the "Undang-undang Tubuh Negeri Johor" which disallowed the Sultan of Johor from performing actions that might threaten the sovereignty of Johor.As a response of the protest, he hosted the first UMNO's first general assembly at his palace in Johor Bahru on May 1946.