Why did Muhammad Ahmad al-Mahdi's claim appear meaningful at the end of the 13th Islamic century?

Muhammad Ahmad al-Mahdi’s claim of being the mahdi—a divinely guided restorer of the faith—carried significant weight at the end of the 13th Islamic century because of long-standing traditions regarding religious renewal.12

In the Islamic calendar, the turn of a century is traditionally associated with the emergence of a mujaddid, or a "renewer" of the faith. While the mahdi is an eschatological figure expected to appear before the end of the world, the concept of the mujaddid is cyclic, with powerful religious movements frequently emerging at the end of every century since AH 200.12

By proclaiming his mission in 1881, which coincided with the end of the 13th century AH, Muhammad Ahmad al-Mahdi fulfilled these deep-seated expectations for many Sudanese people. His followers viewed him as a figure who would end an "age of darkness" and herald a new era of light and righteousness. This timing, combined with widespread discontent under Egyptian administration, allowed him to unify diverse groups—including oppressed taxpayers, slave traders, and nomadic tribes—into a powerful movement to purify Islam.23