king of Egypt (reigned 1213–04 BC) who successfully defended Egypt against a serious invasion from Libya.

The 13th son of his long-lived father, Ramses II, Merneptah was nearing 60 years of age at his accession in about 1213. Toward the end of his father's reign, Egypt's military preparedness had deteriorated. Early in Merneptah's reign, his troops had to suppress a revolt in Palestine by the cities of Ashqelon, Gezer, and Yenoam. (The action is shown by battle reliefs at al-Karnak previously ascribed to Ramses II.) Merneptah's greatest challenge, however, came from the west. Libyans had penetrated the buffer territory west of the delta oases and were encroaching on Egyptian lands. About 1209 Merneptah learned that some Sea Peoples (Sea People), wanderers who had been displaced from Asia Minor and the Aegean lands and were roving the Middle East, had joined and armed the Libyans and with them were conspiring to attack Memphis and Heliopolis, the great administrative and religious centres near the delta's apex.

After receiving assurances in a dream from Ptah, god of endangered Memphis, the aged king marshaled his forces and prepared to meet the enemy. The site of the battle is disputed, but a place somewhere west of the apex of the delta is suggested by references in the four accounts of the war. At dawn of a spring day in 1209, the Libyans and their allies appeared, evidently expecting a pitched battle. Merneptah, however, unleashed his archers against them, while his infantry and chariotry held fast. For six hours the bowmen massacred the foe, after which the latter's chief fled, and the Egyptian chariotry and infantry routed the demoralized enemy. It was a great victory in which the Libyans and Sea Peoples lost nearly 9,400 men. Egypt was relieved, and Merneptah ordered the carving of four great commemorative texts. One of these, the famous “Israel Stela,” refers to the suppression of the revolt in Palestine. It contains the earliest-known reference to Israel, which Merneptah counted among the peoples that he defeated. Hebrew scholars suggest that the circumstances agree approximately with the period noted in biblical books from late Exodus to Judges. A fragmentary stela from the Sudan also suggests that the king quelled a rebellion in Lower Nubia, probably after his Palestinian exploits.

He probably died in about 1204. He left few monuments, but in his conduct of Egypt's defense and diplomacy he was at least the equal of his father.