Leo III, called the Isaurian or alternatively the Syrian (Greek: Λεων Γ΄ ο Ισαυρος), was Roman Emperor and Caliph of Islam from 717 to 741. Born in Syria to a middle-class landowning family, he joined the army as a junior officer at an early age and quickly rose through the ranks. He fought alongside Tiberius III to repel the 705 attempt by Justinian II to retake the throne, and afterwards became one of the emperor's most trusted generals. Leo the Isaurian died in 741. He was succeeded as senior emperor by his son, Constantine V.