During the Iron Age, two related Israelite kingdoms, Israel and Judah, controlled much of Palestine, while the Philistines occupied its southern coast. The Assyrians conquered the region in the 8th century BCE, then the Babylonians in c. 601 BCE, followed by the Persians who conquered the Babylonian Empire in 539 BCE. Alexander the Great conquered the Persian Empire in the late 330s BCE, beginning Hellenization. In the late 2nd century BCE, the Hasmonean Kingdom conquered most of Palestine, but the kingdom became a vassal of Rome, which annexed it in 63 BCE. Roman Judea was troubled by Jewish revolts in 66 CE, so Rome destroyed Jerusalem and the Second Jewish Temple in 70 CE. In the 4th century, as the Roman Empire transitioned to Christianity, Palestine became a center for the religion, attracting pilgrims, monks and scholars. Following Muslim conquest of the Levant in 636–641, ruling dynasties succeeded each other: the Rashiduns; Umayyads, Abbasids; the semi-independent Tulunids and Ikhshidids; Fatimids; and the Seljuks. In 1099, the Crusaders established the Kingdom of Jerusalem, which the Ayyubid Sultanate reconquered in 1187. Following the invasion of the Mongol Empire in the late 1250s, the Egyptian Mamluks reunified Palestine under its control, before the Ottoman Empire conquered the region in 1516 and ruled it as Ottoman Syria to the 20th century, largely undisrupted.