Was Theseus the Son of Aegeus or of Poseidon?

Exploring the origins of the legendary Athenian hero, Theseus, reveals a fascinating blend of history and mythology. Did he truly descend from a mortal king, or was he claimed as the son of the sea god, Poseidon?

Historical vs. Mythological Perspective

Let's consider Theseus as a real person on whom the myths were built. If he was a real individual, he could not have been the son of Poseidon, the god of the sea. However, historical figures often inspire mythic tales, and in this case, a king of Athens named Aegeus fits the bill perfectly.

Aegeus - The King Who Fitted the Bill

Aegeus, the king of Athens, was a plausible human father for Theseus. Athenian tradition spoke of a king who united the entire Attica region into a single polis, or city-state, named Athens. This king was known to have fought bandits, eradicated beasts, and ended the tribute that Athens had to pay to an overlord from Crete. These deeds were within the realm of what an Athenian king of the time might accomplish, without the fantastical elements of fighting a half-bull opponent.

Ancient Greek Views on Divine Descent

By the classical era, ancient Greeks began to question whether heroes like Theseus had divine parents. In Euripides' play, Helen, Helen presents herself as the daughter of Tyndareus, with Zeus as a father only in the legend:

Nor is my fatherland unknown to fame, even Sparta or my sire Tyndareus; for a legend tells how Zeus, winged his way to my mother Leda's breast in the semblance of a bird, even a swan, and thus, as he fled from an eagle's pursuit, achieved his amorous purpose. If this tale be true, my name is Helen.

Euripides then plays with the duality:

PORTRESS
Beneath this roof dwells the daughter of Zeus Helen.
MENELAUS
What meanst thou? What is it thou hast said? Repeat, I pray, thy words.
PORTRESS
The daughter of Tyndareus is here, who erst in Sparta dwelt.
MENELAUS
Whence came she? What means this business?

Helen, despite her divine parentage in the legend, does not believe herself to be the daughter of Zeus. This reflects how, in the classical era, heroes were increasingly seen as having mortally born, rather than divine, parents.

Theological Shift and Hero Cult

By the Hellenistic period, there was a revival of hero worship. Great kings, such as Alexander the Great, began to be attributed divine parentage. The legend that Alexander was the son of Zeus, rather than the king Philip, is a prime example of this trend. This practice of attributing divine parentage to kings after they achieved great deeds was not uncommon among ancient Greeks, as seen in the case of Roman emperors as well.

Thus, while it is entirely plausible to think of Theseus as the son of Aegeus, who united Athens and fought great battles, the cult of Theseus honored him as the son of Poseidon more as a form of hero worship rather than historical fact. The transition from a mortal father to a divine one aligns with the evolving views of ancient Greeks regarding divine descent.