Aegeus

He won all the contests at the Panathenaic festival at Athens, whose king, Aegeus, slew him out of jealousy.

The tribute continued to be paid until Theseus, son of Aegeus, went to Crete as one of the seven.

Aegeus was under a curse of childlessness, and his desolate condition suggests to Medea the ultimate form of her vengeance.

Thus, the meeting with Aegeus is probably not the free invention of Euripides, but one of the data supplied to him by his subject.

Medea might take them with her to Athens and trust to the hope of Aegeus' being able and willing to protect them.