This is one of the very few cross-cultural pairings on this site that the ancient world made itself, in writing, in stone. Hermanubis is not a modern conjecture. He is an attested deity of Roman-period Egypt, with statues, coins and inscriptions, produced by a society in which Greek and Egyptian religion had been sharing a country for centuries. That makes the comparison a historical fact to be explained rather than a resemblance to be argued.
What the syncretism actually produced
The fused figure appears in Greco-Roman Egypt as a young man in Greek dress with a jackal's head, sometimes carrying a caduceus — the herald's staff — and sometimes a palm. A well-known marble in the Vatican collections shows exactly this combination. His name is attested on coinage from Alexandria and in inscriptions, and he sits alongside the larger and more deliberate creation of the same period, Serapis, in a religious landscape where the Ptolemaic state had a direct interest in gods both populations could recognise.
The logic of the fusion is easy to read once you know what each figure was for. Both are associated with the passage of the dead; both are guides rather than judges; both are approachable in a way that the rulers of the underworld are not. That is a real functional overlap and it explains why the identification took, when so many others did not.
But the functions are not the same function
Look closer and the two jobs pull apart.
Anubis is fundamentally a mortuary technician. He is the god of embalming, and the priest who performed the wrapping wore a jackal mask to be him for the duration. He guards the necropolis, attends the mummification, and — in the judgement scene — operates the balance itself, adjusting the plumb. He is present at the most technical and most anxious moment of Egyptian religion, and his role is to make sure the process is done correctly. He is on the deceased's side, professionally.
Hermes in his guide-of-souls role is doing something much smaller. He conducts the shades of the suitors down to the meadow of asphodel with a golden wand, herding them as they squeak like bats — a passage in the Odyssey that is one of the few places the function is actually narrated. It is one office among many for him, and it is a transport role. He does not prepare the body, assess the person, or attend a trial.
The difference in weight is telling. Egypt built an entire industry around death and gave Anubis its most technical station. Greece gave the job of walking the dead downstairs to a god who also delivered messages, invented the lyre and protected merchants.
The jackal and the herald's staff
Each figure's iconography reveals a different theory of what a guide is.
The jackal was, on the standard reading, chosen because jackals scavenged desert cemeteries: the animal that endangered the tomb was elevated into the god who protected it. That is a piece of applied religious reasoning with real force — you neutralise a threat by appointing it.
The caduceus is a herald's badge, and heralds in the Greek world were legally inviolable. What Hermes carries is a diplomatic passport. It is worth noting, since the confusion is now endemic, that the two-snake herald's staff is not the single-snake rod of Asclepius, and its widespread use as a medical emblem is a nineteenth-century American mistake — a topic that belongs to symbol history more than to religion.
The boundary logic that made the merge possible
Both gods do the same structural job in their pantheons: they cross lines that others cannot. Hermes moves between Olympus, earth and the underworld, and his older cult objects — the herm, a pillar with a head and genitals — stood at boundaries, doorways and crossroads. Anubis stands at the desert edge, where the cultivated land stops and the cemeteries begin, which in Egyptian geography is the most consequential boundary there is.
A Greek settler in Egypt looking for the local equivalent of the god who stands at the threshold would find Anubis without much difficulty. That is how interpretatio generally worked: not by matching mythologies, which rarely match, but by matching positions.
What each culture believed happened next
Here the comparison stops being useful and starts being a contrast, because the destinations differ completely.
Anubis leads the deceased into the Hall of Two Truths, where the heart is weighed against the feather of Maat and the verdict determines whether the dead person proceeds to the Field of Reeds or is destroyed by Ammit. There is a defence, a procedure and an outcome contingent on conduct.
Hermes leads the shades to a place where, in the older Greek picture, nothing is assessed at all. The escort is the whole service. There is no reason for a Greek guide of souls to be present at a trial, because in the tradition he comes from there is no trial. That divergence is developed at the underworlds compared.
The wider category
Neither god is a reaper, and neither is a summoner. The distinctions between announcing a death, escorting the dead, and coming to collect them are set out at those who come for you, and the four different transactional models — payment, judgement, selection, arrest — at who takes the dead. For the individual entries, see Anubis, Hermes, Charon, Thoth and Wepwawet — the last of whom is the Egyptian canid most people mistake for Anubis in images, and whose name means "opener of the ways".
Questions this pairing prompts
Was Hermanubis worshipped by Egyptians or by Greeks? By a mixed population in a Hellenised urban environment, principally Alexandria and the Fayum, and the evidence — Greek-language inscriptions, Greek-style sculpture, an Egyptian head — reflects that mixture rather than either community on its own. Traditional Egyptian temple religion in the countryside carried on with Anubis unmodified.
Did the Greeks think Anubis was ridiculous? Some did, loudly. Animal-headed gods were a recurring target of Greek and Roman satire, and a Roman poet mocks "barking Anubis" in a famous line about Egyptian gods opposing the Roman ones. That contempt coexisted with genuine devotion to Egyptian cults elsewhere in the same society, including among Romans of high rank.
Is Anubis the god of the dead? No, and this is the most common error about him. Osiris rules the realm of the dead; Anubis handles the transition. Egyptian tradition even accounts for the change explicitly, with Anubis described in some texts as having ceded the position when Osiris came into it. He is the specialist, not the sovereign.
Why does Hermes get this job at all? Because it follows from what he already is. A god of boundaries, roads, transitions and messages is the obvious candidate to conduct someone across the last boundary, and the Greeks appear to have reasoned exactly that way — his underworld epithet is an extension of his ordinary function rather than a separate identity, which is precisely why the role is so much thinner than Anubis's.