For years the consensus has been that when the Romans left the economy of Britain took a big hit. New research published in Antiquity and summarized in Science (389:1077, 9/11/25) shows that, at least in Yorkshire, this was not so.
Excavations have been going on at Aldborough (Isirium Brigantum) since the 19th century. It was recently discovered that there was an abandoned bed of the river Ure in the area. As this was undisturbed soil, a 6-meter-long core was drilled and analyzed for the waste of the iron and lead mining and smelting which was the main economic activity in the area.
The core showed that the mining and smelting continued at roughly constant levels through the 6th century C.E. There were, of course, ups and downs due to local conditions—local wars, plagues, etc., but the overall level remained fairly constant.
To me this merely shows that generalizing about a broad geographical area, Britain, on the basis of evidence from a small subarea, southeastern Britain, can lead to wrong conclusions.
By Daniel A. Bronstein, Professor Emeritus, Michigan State University