The Egyptian Gods got everywhere in the Roman Empire even Britain.
Epigraphic evidence (inscriptions) provides strong proof for a temple to Serapis (Serepeum) in York and a temple to Isis (Iseum) in London. There was possibly more temples in the major cities, especially those with links to trade, governance and the military.
The Iseum in London is demonstrated with an inscriptions from an altar (which was later used in the London walls) and a jug with an inscription saying it belonged to the Iseum. Even though jugs were common symbols of Isis, this jug is often presumed to belong to a tavern located near to the Iseum. It was found in Southwark, which was then the marshy south bank opposite the city.
From this evidence it is hard to locate the temple or to work out how big and important it might have been.
Although there is not evidence for a Serapeum in London, we might presume he was worshipped alongside Isis given the fact that this was a common practice elsewhere in Greek and Roman world. A bust of Serapis was found in the London Mithraeum, alongside other statues identified as a river god and a male god holding a cornucopia and a steering oar.
The Eastern Gods were popular in the second and third centuries CE. Mithras appeared to have been the most popular “oriental” god, but perhaps the picture is more complicated than at first seems (especially if Serapis may have also been worshipped in the Mithraeum).
Other artefacts that have been found include little bronze weights depicting the goddess, figurines of Harpocrates and small amulets.
A particular beautiful silver figurine of Harpocrates was found in the Thames. It shows the god with a dog, a tortoise and a bird.
A tiny figurine of Harpocrates found in Chester might have had healing uses. Pliny the Elder wrote that gems with Harpocrates on were used as health magic.
The most intriguing finds are lamps. Lamps were used in the Isis religion across the Roman Empire. They often portray the four gods (Isis, Serapis, Anubis and Harpocrates) either in groups or on their own. Although the numbers are much smaller for Roman Britain, the lamps buck the wider trend and more show Anubis than any other god.
Perhaps this is linked to importance of dogs in Celtic Religion. Dogs have been found at wells and healing centres in Britain. They had a religious role in Britain that is hard to identify now.
Who worshipped these gods? It is hard to know. Clifford Herschel Moore said that evidence for the Eastern gods could be found in centres with Roman soldiers. He argued that the inhabitants of Roman Britain were not profoundly affected by the Eastern religions.
Other scholars, such as Massie have argued that the gods were worshipped by Egyptians (or Greeks) in Britain.
Yet London has always been a multicultural city and so it would, perhaps, not be unsurprising if the gods did enjoy a more open welcome than previous suspected.
Further study is needed…