In ancient Egyptian religion, the cobra goddess who was tutelary goddess of Lower Egypt and, with the vulture-goddess Nekhbet of Upper Egypt, protector of the king. She was nurse to the infant god Horus and helped his mother, Isis, protect him from his uncle Seth. She was later identified with Leto. She is depicted as a cobra twined around a papyrus stem.
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Buto originally was two cities, Pe and Dep, which merged into one city that the Egyptians named Per-Wadjet. The goddess Wadjet was its local goddess, often represented as a cobra, and she was considered the patron deity of Lower Egypt. Her oracle was located in her renowned temple in that city. An annual festival held in the city celebrated Wadjet. Her image formed the royal crown, the Uraeus, worn by the rulers of Lower Egypt. It encircled their heads and the cobra flare and head extended from their foreheads. Wadjet was closely associated in the Egyptian pantheon with Bast the fierce goddess depicted as a lioness warrior and protector, a sun goddess whose eye later became the eye of Horus of the eye of Ra, the Lady of Flame. The city also contained a sanctuary of Horus and much later, became associated with Isis.
The city was an important site in the Predynastic era of Ancient Egypt that includes the cultural developments of ten thousand years from the Paleolithic to 3100 B.C. Archaeological evidence shows that Upper Egyptian culture replaced the Buto-culture at the delta when Upper and Lower Egypt were unified, and the replacement is considered important evidence for the unification of the two portions of Egypt into one entity. At that time Wadjet joined Nekhbet, who was represented as a white vulture and held the same position as the patron of Upper Egypt, and together they were known as the two ladies  who were the patrons of the unified Egypt. The image of Nekhbet joined Wadjet on the Uraeus that would encircle the crown of the pharaohs who ruled the unified Egypt.
Being called Buto by the Greeks during Ptolemaic Egypt, a Greek dynasty ruling from 305 B.C. to 30 B.C., it was the capital town, or according to Herodian, merely the principal village of the Nile Delta, which Herodotus (l. c.) calls the Chemmite nome; Ptolemy, the Phthenothite nome (Φθενότης, iv. 5. § 48), and Pliny the Elder, (v. 9. s. 11), Ptenetha.
The Greek historians record that town was celebrated for its monolithite temple and oracle of the goddess Wadjet (Buto) (Herod. ii. 155) (Aelian. V. Hist. ii. 41), whom the Greeks identified with Leto or Latona. A yearly feast was held there in honour of the goddess.
They noted that at Buto there was also a sanctuary of Horus (associated by the ancient Greeks with Apollo) and of Bastet (associated with Artemis). (Champollion, l'Egypte, vol. ii. p. 227.) In Egyptian mythology, Bast (also spelled Bastet, Baset, Ubasti, and Pasht) is an ancient goddess, worshipped at least since the Second dynasty of Egypt, which is dated 2890 B.C. to 2690 B.C. The centre of her cult was in Per-Bast (Bubastis in Greek), which was named after her. Originally she was viewed as the protector goddess of Lower Egypt, and consequently depicted as a fierce lioness. Indeed, her name means devourer. As protector, she was seen as defender of the pharaoh (and consequently of the later chief god, Ra), who was a solar deity, gaining her the titles Lady of Flame and Eye of Ra. Bast was originally a sun goddess, but later changed by the Greeks to a goddess of the moon. In Greek mythology, Bast is also known as Aelurus.
According to these same late sources, the shrew mouse was worshipped at Buto. (Herod. ii. 67.)