Necho I, ruler of the city of Sais, died in 664 BCE fighting the Kushites, invaders from Nubia, on the behalf of his Assyrian overlords. The Assyrians rewarded his son, Psamtek I, with the governorships of Memphis and Sais. While careful to maintain cordial relations with the Assyrians, Psamtek amassed an army of Carian and Greek mercenaries, and established alliances with Lydia and the Tyrant of Samos. Within a period of months, the four Chiefs of Ma (ancient Libya) submitted to his authority. The eastern delta proved more stubborn but finally, in 656 BCE, the king of the ancient capital of Tanis recognized his rule, rendering him undisputed sovereign of Lower Egypt. Upper Egypt, however, retained close ties with the Kushites. Psamtek I addressed this situation by sailing with a powerful fleet to Thebes and securing the appointment of his daughter Nitocris as Votaress of Amun, a position with great religious, political and financial clout. At a stroke, Upper Egypt was effectively under his control.