Removed superfluous stuff
Slaves were an important part of early mediaeval society and appear in large numbers in charters and Domesday Book, but the evidence for them is mostly fragmentary and widely scattered.
Apart from Ireland, many slaves were taken to Europe for sale. Rouen, in Normandy, was a major trading centre for goods seized by the Vikings - the Normans were known to have used domestic slaves- and it was a convenient location for pirates to off-load captives taken in raids along the English coastline. It seems that all the big markets were slave trading centres including, perhaps, Jorvik and London.
After the Norman conquest, the slave trade came under pressure, even the king received fourpence for every slave sold
(Vassal Added Tax?). The social disruption and misery that organised slaving caused became more and more difficult to accept. At the Westminster Council of 1102, it was ruled that 'no one is henceforth to presume to carry on that shameful trading whereby heretofore men used in England to be sold like brute beasts.'
# Pelteret, D, 'Slave raiding and slave trading in early England', Anglo-Saxon England 9 (1981), pp99-114