According to the accounts of Hesiod and mythographer Apollodorus, the Cyclopes had been imprisoned by their father Uranus. Zeus later freed the Cyclopes, and they repaid him by giving him the thunderbolt. The Cyclopes provided for Hesiod, and others theogony-writers, a convenient source of heavenly weaponry, since the smith-god Hephaestus—who would eventually take over that role—had not yet been born. According to Apollodorus, the Cyclopes also provided Poseidon with his trident and Hades with his cap of invisibility, and the gods used these weapons to defeat the Titans.