Athamas was a king of the region of Boeotia in Greek mythology, son of Aeolus and Enarete. He had three wives; the goddess Nephele; the daughter of Cadmus, Ino; and Themisto. With Nephele he had three children, the twins Phrixus and Helle, and Makistos. He and Ino had two children, Learchus and Melicertes.
Ino hated the children from her husband's first marriage, and especially the twins, so she devised a plot to kill them. She collected all crop seeds from the town, and roasted them; the farmers, seeing that their crops wouldn't grow, sent people to ask an oracle for a solution. Ino bribed the messengers to say that the oracle asked for the sacrifice of the twins. Athamas had no other choice but agree with the sacrifice, but just before the children were killed, a flying golden ram that was sent by Nephele saved Phrixus and Helle. The ram flew day and night; at some point, Helle looked down despite her mother's warning, and fell from the ram; she died at the sea now called Hellespont, which was named after her. Phrixus survived the whole flight and went to Colchis, where the king Aeetes welcomed him. Phrixus gave the ram's golden fleece as a gift, which later became the object of desire for Jason and the Argonauts.
Meanwhile, back in Boeotia, Ino helped raise her nephew, the god Dionysus,which triggered Hera's jealousy. The queen of gods inflicted madness upon Athamas, who slew his son Learchus, while Ino and Melicertes fell into the sea in a desperate attempt to evade the maddened king. After he recovered and full of guilt for his son's death, Athamas fled Boeotia and went to Phthiotis, where he married Themisto. The couple had a number of children, but soon afterwards, Athamas returned to Ino. Themisto wanted to take revenge by killing Ino's children, so she dressed them in black clothes, while her own were dressed in white. Ino switched the clothes without Themisto knowing, who ended up killing her own children.
Athamas Is also called Athamus.