Anubis is the Greek name for the ancient jackal-headed god of the dead in Egyptian mythology whose hieroglyphic version is more accurately spelled Anpu (also Ano-Oobist, Anoubis, Anupu, Anbu, Wip, Ienpw, Inepu, Yinepu, Inpu, or Inpw). He is also known as Sekhem Em Pet. Prayers to Anubis have been found carved on the most ancient tombs in Egypt; indeed, the Unas text (line 70) associates him with the Eye of Horus. He serves as both a guide of the recently departed and a guardian of the dead.

No public procession in Egypt would be conducted without an Anubis to march at the head, the "go-between" of gods and men. The ancient Egyptians swore "by the Dog" when making oaths they would not break.

Anubis was the guardian of the dead, who took souls to the Underworld and protected them on their journey. It was he who deemed the deceased worthy of becoming a star. Ancient Egyptian texts say that Anubis silently walked through the shadows of life and death and lurked in dark places. He was watchful by day as well as by night. He also weighed the heart of the dead against the feather symbol of Ma'at, the goddess of truth. One of the reasons that the ancient Egyptians took such care to preserve their dead with sweet-smelling herbs was that it was believed Anubis would check each person with his keen canine nose. Only if they smelled pure would he allow them to enter the Kingdom of the Dead.

Anubis was portrayed as a jackal-headed man/god, or as a jackal wearing ribbons and holding a flagellum, a symbol of protection, in the crook of its arm. Some think that he was not pictured as a jackal but as a dog, fox, wolf, or hybrid instead. Very rarely is he ever shown fully human. Anubis was always shown as a black jackal or dog, even though real jackals are typically tan or a light brown. To the Egyptians black was the color of regeneration, death, and the night. It was also the color that the body turned during mummification.

The reason for Anubis' animal being canine is based on what the ancient Egyptians themselves observed of the creature - dogs and jackals often haunted the edges of the desert, especially near the cemeteries where the dead were buried. In fact, it is thought that the Egyptians began the practice of making elaborate graves and tombs to protect the dead from desecration by jackals. A statue of Anubis, jackal-form, was found in Tutankhamen's tomb. When pet dogs died, they were mummified and buried in temples dedicated to Anubis.

Originally, in the Ogdoad system, he was god of the underworld. He was said to have a wife, Anput (who was really just his female aspect, her name being his with an additional feminine suffix: the t), who was depicted exactly the same, though feminine. He is also listed to have taken to wife the feminine form of Neheb Kau, Nehebka, and Kebauet. Kebauet, the Goddess of cold water, is also listed as his daughter in some places. His father was originally Ra in many papyrus records which were found in pyramids, (Anubis was the fourth son of Ra.) But in after ages, his father was said to be Osiris, as he was the god of the dead, and his mother was said to be Nephthys. Anubis was identified as the father of Kebechet, the goddess of the purification of body organs due to be placed in canopic jars during mummification.

As one of the most important funerary rites in Egypt involved the process of embalming, so it was that Anubis became the god of embalming, in the process gaining titles such as "He who belongs to the mummy wrappings", and "He who is before the divine [embalming] booth". High priests often wore the Anubis mask to perform the ceremonial deeds of embalming. It also became said, frequently in the Book of the Dead, that it had been Anubis who embalmed the dead body of Osiris (which would make him the older sibling of Horus), with the assistance of the other main funerary deities involved - Nephthys and Isis. Having become god of embalming, Anubis became strongly associated with the (currently) mysterious and ancient imiut fetish, present during funerary rites, and Bast, who by this time was goddess of ointment, initially became thought of as his wife.

Following the merging of the Ennead and Ogdoad belief systems, as a result of the identification of Atum with Ra, and their compatibility, Anubis became considered a lesser god in the underworld, giving way to the more popular Osiris. Indeed, when the Legend of Osiris and Isis emerged, it was said that when Osiris had died, Osiris' organs were given to Anubis as a gift.

Since he had been more associated with beliefs about the weighing of the heart than had Osiris, Anubis retained this aspect, and became considered more the gatekeeper and ruler of the underworld, the "Guardian of the veil" (of "death"). As such, he was said to protect souls as they journeyed there, and thus be the patron of lost souls (and consequently orphans). Rather than god of death, he had become god of dying, and consequently funeral arrangements. It was as the god of dying that his identity merged with that of Wepwawet, a similar jackal-headed god, associated with funerary practice, who had been worshiped in Upper Egypt, whereas Anubis' cult had centered in Lower Egypt.

However, as lesser of the two gods of the underworld, he gradually became considered the son of Osiris, but Osiris' wife, Isis, was not considered his mother, since she too inappropriately was associated with life. Instead, his mother became considered to be Nephthys, who had become strongly associated with funerary practice, indeed had in some ways become the personification of mourning, and was said to supply bandages to the deceased. Subsequently, this apparent infidelity of Osiris was explained in myth, in which it was said that a sexually frustrated Nephthys had disguised herself as Isis in order to appeal to her husband, Set, but he did not notice her as he was infertile (some modern versions depict Set as a homosexual, but these have little bearing on the original myth). However, Isis' husband Osiris mistook Nephthys for his wife, which resulted in Anubis' birth. Other versions of the myth depict Set as the father, and it remains unclear as to whether Set was truly infertile or not.

In later times, during the Ptolemaic period, as their functions were similar, Anubis came to be identified as the Greek god Hermes, becoming Hermanubis. The centre of this cult was in uten-ha/Sa-ka/ Cynopolis, a place whose Greek name simply means "city of dogs". In Book XI of "The Golden Ass" by Apuleius, we find evidence that the worship of this god was maintained in Rome at least up to the 2nd century. Indeed, Hermanubis also appears in the alchemical and hermetical literature of the Middle Ages and the Renaissance.

Although the Greeks and Romans typically scorned Egypt's animal-headed gods as bizarre and primitive (they mockingly called Anubis the "Barker"), Anubis was sometimes associated with Sirius in heaven, and Cerberus in hell.

Early Christians were also repulsed by Anubis; the writer Tertillian claimed that the Egyptians practiced a "despicable religion" in which the worshiper is "led like a slave by the greedy throat and filthy habits of a dog." Although it is true that his two emblematic creatures, the jackal and the dog, were in the ancient world notorious scavengers, one of the main functions of Anubis was to release the human body at death from the uncleanness that possessed it. He washed the body, embalmed it, perfumed it with myrrh, wrapped it with clean linen and received it at the door of the tomb – to the Egyptians he was "Lord of the Cleansing Room."