Egypt in 1889, but British-led Egyptian troops defeated the Ansar at Tushkah. The failure of the Egyptian invasion broke the spell of the Ansar's invincibility. The Belgians prevented the Mahdi's men from conquering Equatoria, and in 1893, the Italians repelled an Ansar attack at Agordat (in Eritrea) and forced the Ansar to withdraw from Ethiopia. In the 1890s, the British sought to re-establish their control over Sudan, once more officially in the name of the Egyptian Khedive, but in actuality treating the country as a British colony. By the early 1890s, British, French, and Belgian claims had converged at the Nile headwaters. Britain feared that the other powers would take advantage of Sudan's instability to acquire territory previously annexed to Egypt. Apart from these political considerations, Britain wanted to establish control over the Nile to safeguard a planned irrigation dam at Aswan. Herbert Kitchener led military campaigns against the Mahdist Sudan from 1896 to 1898. Kitchener's campaigns culminated in a decisive victory in the Battle of Omdurman on 2 September 1898. A year later, the Battle of Umm Diwaykarat on 25 November 1899 resulted in the death of Abdallahi ibn Muhammad, subsequently bringing to the end of the Mahdist War. Anglo-Egyptian Sudan (1899–1956) In 1899, Britain and Egypt reached an agreement under which Sudan was run by a governor-general appointed by Egypt with British consent. In reality, Sudan was effectively administered as a Crown colony. The British were keen to reverse the process, started under Muhammad Ali Pasha, of uniting the Nile Valley under Egyptian leadership and sought to frustrate all efforts aimed at further uniting the two countries. Under the Delimitation, Sudan's border with Abyssinia was contested by raiding tribesmen trading slaves, breaching boundaries of the law. In 1905 Local chieftain Sultan Yambio reluctant to the end gave up the struggle with British forces that had occupied the Kordofan region, finally ending the lawlessness. The continued British administration of Sudan fuelled an increasingly strident nationalist backlash, with Egyptian nationalist leaders determined to force Britain to recognise a single independent union of Egypt and Sudan. With a formal end to Ottoman rule in 1914, Sir Reginald Wingate was sent that December to occupy Sudan as the new Military Governor. Hussein Kamel was declared Sultan of Egypt and Sudan, as was his brother and successor, Fuad I. They continued upon their insistence of a single Egyptian-Sudanese state even when the Sultanate