In the early 7th century, Muhammad’s steady unification of the warring tribes of Arabia appeared to be an insignificant sideshow in a remote backwater. What mattered was the clash of the Sassanid and Byzantine Empires in all-out war (602–28). Fortunes swung violently: the Sassanids captured Syria, Palestine and Egypt, then laid siege to Constantinople itself, until the emperor Heraclius bought them off. Heraclius then rebuilt his army and counterattacked, with victory after victory, regaining almost all his lost territories. When peace was agreed the empires were devastated and exhausted, and proved easy meat for the Islamic upstarts who would burst from the south. Remote from this sturm und drang, a string of Christian kingdoms – Nobatia, Makkuria, Alwa and Axum had quietly flourished between Egypt and the Horn of Africa. Little Makkuria would prove a doughtier foe of Islamic armies than the mighty Sassanids and Byzantines, twice repulsing their invasions in 642 and 652.
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