Having occupied Wales for more than 300 years – since AD 78 – the Roman army was progressively withdrawn from the late 4th century. Roman authorities ceased dispatching coins to Britain to pay the remaining troops early in the AD 400s, and by the end of the first decade of the 5th century, Britain was no longer part of the Roman Empire. However, the end of Roman military control probably had little impact on the majority of people in Wales. Mass-produced pottery and other Romanised goods were no longer available, but in rural communities these had never wholly replaced locally produced artefacts of wood and iron, nor the production of textiles, tools, and querns – all based on the fundamental craft skills of the later prehistoric way of life, dominated by the demands of the agricultural year.
Living conditions might have become just a little easier with the demise of Roman taxation, though, and as the old order faded, new patterns of power were established. Local leaders began to emerge from among army veterans, civic officials, and native power-brokers – anyone with the ambition to seize and hold power. To support their retinues, they no doubt continued to demand a proportion of everyone’s agricultural surplus in return for keeping the peace and providing rough justice.
Much more of an impact is likely to have been felt a century or so later, because of climate change and disease. Britain and Ireland enjoyed a benign climate during the Roman period that was warmer and drier than previously. From AD 536, though, the atmospheric dust from a series of major volcanic eruptions centred on north and central America brought about abrupt and prolonged summer cooling across the northern hemisphere, lasting into the mid-7th century. A cooler and wetter climate increased the chances of crop failure and had an impact on yields. Wetlands became wetter, and uplands were covered in snow for longer, reducing the length of the grazing season for livestock and increasing the demand for winter fodder. The Annales Cambriae (‘Annals of Wales’, which began to be compiled at St Davids in the late 8th century but incorporated earlier material) contain a record of mortalitas in Britain in 537, presumably from famine following severe weather.
