The Hittites first came to prominence in the 17th century BCE, and managed to master the forging of iron, which gave them combat edge in the durability of their weaponry over Bronze Age rivals. In an early imperial phase, they reached, and sacked, Babylon (1531 BCE) but then lapsed into a period of internal division before a resurgence under Kings Suppiluliuma I (1344–1322 BCE) and Mursili I (1321–1295 BCE), during whose reigns they conquered most of Anatolia, and annexed much of Syria from, respectively, the Mittani and the Egyptians. In 1274 BCE, they were still formidable enough to repulse a powerful pharaoh, Rameses II, at the Battle of Kadesh. Thereafter, they spiralled rapidly into decline, eclipsed by the repeated depredations of the Sea Peoples from the south, and nomadic Kashka to their north. Their residual dominions would be overwhelmed by successive Assyrian conquerors in the 12th century BCE.