Caithness Field Club

The Black Rat's Home In Roman Britain

Further proof that black rats - carriers of the infamous bubonic plague - entered Britain long before the Middle Ages has come with the discovery of bones of Rattus rattus in Roman remains at two sites in the City of London.

Evidence that black rats were present in Britain in Roman times first came in 1979, when James Rackham (Antiquity, vol. 53, p. 112) reported finding rat bones in a filled-in well in York dating from late Roman times or soon afterwards (about the fifth century AD). The dates of the finds in London are earlier - mid-third century AD for a well in Fenchurch Street and fourth century at Crosswall. Archaeologists have also found bones of the black rat probably contemporary with those at York, at Wroxeter near Shrewsbury. These recent discoveries should dispel any lingering doubts that black rats were widespread in Britain in the first centuries AD, and that epidemics of plague occurred in Britain well before the Black Death in medieval times. Before the discovery at York, historians had assumed that the black rat was not introduced into Britain until the 11th or 12th centuries, when returning Crusader ships brought it from the Holy land. The many contemporary records of unidentified "pestilencies" in Roman and Anglo-Saxon Britain have been either ignored or explained away as outbreaks of smallpox or some other contagious disease. However, it seems unlikely that Britain could have escaped the plague epidemics that swept around the Mediterranean area and across Europe during the last centuries BC and the first centuries AD.

Philip Armitage, Barbara West and Ken Steedman, members of the Museum of London's archaeological team who describe the rat remains found in London (London Archaeologist, vol. 4 p.375), are in no doubt that the bones discovered at Fenchurch Street and Crosswall are R. rattus, not its close relative the common or brown rat (R. norvegicus), which arrived in Britain only in the late 17th or early 18th century. They are also certain that live black rats in modern times could not have burrowed down into the Roman deposits.

The original homeland of black rats is south-east Asia and it is easy to envisage how the animals spread around the ancient world as trading by sea Increased. They seem to have reached Egypt in large numbers by the last centuries BC, Italy (Pompeii) by the second century BC to First century AD, and Switzerland and Germany by at least the first century AD, according to Armitage and his colleagues.

York and London were thriving administrative and trading centres by Roman times. York had strong connection with Rhineland and Bordeaux, and black rats could easily have slipped off cargo boats from continental ports. London's black rats are more likely to have come from the Mediterranean.

There remains a gap in British records of black rats from about the sixth to eighth centuries. It is not yet known if this gap reflects the absence of the animal in the Dark Ages or merely that archaeologists have not looked hard enough for black-rat bones. Bones of rats and other small mammals are difficult to find in archaeological deposits but the wet-sieving techniques now used are a great improvement on earlier methods; moreover faunal records at sites are now much better than they used to be. At York, the black rat regularly occurs from Norman times back to the 9th century, and Terry O'Connor of York University believes that the animals continued to survive without re-introduction, in the Anglo-Saxon period. However, this may not have been the case elsewhere in Britain.

(Reprinted from the New Scientist, No. 1422, 20th September 1984)