Between the thirteenth and sixteenth centuries the Egyptian Sudan became a congeries of Mohammedan kingdoms with Arab, mulatto, and Negro kings. Far to the west, near Lake Chad, arose in 1520 the sultanate of Baghirmi, which reached its highest power in the seventh century. This dynasty was overthrown by the Negroid Mabas, who established Wadai to the eastward about 1640. South of Wadai lay the heathen and cannibals of the Congo valley, against which Islam never prevailed. East of Wadai and nearer the Nile lay the kindred state of Darfur, a Nubian nation whose sultans reigned over two hundred years and which reached great prosperity in the early seventeenth century under Soliman Solon. Before the Mohammedan power reached Abyssinia the Portuguese pioneers had entered the country from the east and begun to open the country again to European knowledge. Without doubt, in the centuries of silence, a civilization of some height had flourished in Abyssinia, but all authentic records were destroyed by fire in the tenth century. When the Portuguese came, the older Axumite kingdom had fallen and had been succeeded by a number of petty states. The Sudanese kingdoms of the Sudan resisted the power of the Mameluke beys in Egypt, and later the power of the Turks until the nineteenth century, when the Sudan was made nominally a part of Egypt. Continuous upheaval, war, and conquest had by this time done their work, and little of ancient Ethiopian culture survived except the slave trade. The entrance of England into Egypt, after the building of the Suez Canal, stirred up eventually revolt in the Sudan, for political, economic, and religious reasons. Led by a Sudanese Negro, Mohammed Ahmad, who claimed to be the Messiah (Mahdi), the Sudan arose in revolt in 1881, determined to resist a hated religion, foreign rule, and interference with their chief commerce, the trade in slaves. The Sudan was soon aflame, and the able mulatto general, Osman Digna, aided by revolt among the heathen Dinka, drove Egypt and England out of the Sudan for sixteen years. It was not until 1898 that England reentered the Sudan and in petty revenge desecrated the bones of the brave, even if misguided, prophet.