The Akītu (New Year Festival)
Once a year the king was stripped, struck, and made to swear his innocence before the god who alone could renew his crown.
Also: akitu · akītu · New Year festival · Babylonian New Year · Marduk procession · humiliation of the king
The akitu was the most important festival of the Mesopotamian year, celebrated above all at Babylon in the spring. Over several days the gods' statues processed, the creation epic Enuma Elish was recited to re-proclaim Marduk's victory and kingship, and the king underwent a striking rite in which the high priest stripped him of his insignia, struck his cheek, and made him declare before Marduk that he had not sinned against the city — before his rule was renewed for another year. The festival renewed cosmos, kingship, and community together, fixing the destinies of the year ahead.
In short
The great New Year festival, most famously the spring akītu of Babylon, at which Marduk's kingship was renewed, Enuma Elish was recited, the king's office reaffirmed, and the gods' destinies fixed for the year.
Where it’s found
Babylonian akītu ritual texts and the recitation of Enūma Eliš (akkadian-pending; Foster; Bidmead, The Akītu Festival)
How the idea developed across Sumer, Babylon & Assyria
The Babylonian akītu and its 'humiliation of the king' rite are best documented for the first millennium; reconstructions partly depend on late and fragmentary ritual texts, so some details are uncertain. Earlier and other-city New Year observances existed but differed; do not retroject the full Babylon script onto all periods.
The full 'humiliation of the king' script is reconstructed largely from late, fragmentary ritual texts; some details are uncertain and should not be retrojected to all periods.