From his announcement of the Mahdiyya in June 1881 until the fall of Khartoum in January 1885 , Muhammad Ahmad led a successful military campaign against the Turco-Egyptian government of the Sudan ( known as the Turkiyah ) .
From his announcement of the Mahdiyya in June 1881 until the fall of Khartoum in January 1885 , Muhammad Ahmad led a successful military campaign against the Turco-Egyptian government of the Sudan .