Who was the ibis-headed god of writing and wisdom?

The ibis-headed Egyptian god of writing and wisdom was Thoth.

Thoth was a deity of writing, knowledge, wisdom, measurement, magic, science, judgment, and the Moon. Egyptian artists most often depicted him as a man with the head of an ibis, although he could also appear as a baboon. His association with scribes made him one of the principal divine patrons of learning and written knowledge.

Egyptian tradition credited Thoth with inventing hieroglyphic writing. He served as a divine scribe, counselor, and mediator, especially in stories involving Ra, Osiris, Isis, Horus, and Set. In funerary scenes, his role as recorder and judge connected him with the weighing of the heart and the maintenance of cosmic order, or maat.

Thoth’s main cult center was Hermopolis, known in Egyptian tradition as Khmun. The Greeks identified him with Hermes, eventually contributing to the later figure Hermes Trismegistus. This Greek connection is why Hermopolis received its name.

The ibis is the key visual clue, but Thoth was not the only Egyptian deity linked with knowledge or the Moon. Seshat was also associated with writing and measurement, while Ra was chiefly a solar god. Thoth’s distinctive combination of ibis imagery and scribal wisdom makes him the canonical answer.