Yemen Vilayet was a first-level administrative division of the Empire. In the late 19th century, the Zaidis rebelled against the Empire, and Imam Mohammed ibn Yahya laid the foundation of a hereditary dynasty. When he died in 1904, his successor Imam Yahya ibn Mohammed led the revolt against the Empire in 1904–1905, and forced them to grant important concessions to the Zaidis. The Ottoman agreed to withdraw the civil code and restore sharia in Yemen. In 1906, the Idrisi leaders of Asir rebelled against the Ottomans. By 1910 they controlled most of Asir, but they were ultimately defeated by Ottoman Modern Army and Hejazi forces. Ahmed Izzet Pasha concluded a treaty with Imam Yahya in October 1911, by which he was recognized as temporal and spiritual head of the Zaidis, was given the right to appoint officials over them, and collect taxes from them. The Ottomans maintained their system of government in the Sunni-majority parts of Yemen.