What do you know about the Dobunni iron age tribe of Britain?
They were nominally Celtic, a vassal Tribe of the more Warlike Catuvellauni, and they lived along the West side of the Severn Estuary, and up the Avon Valley, which was, (and still is) some of the most productive Farmland in Britain. The deal probably was, that in return for the ready supplies of grain, and cattle that working this land could provide, the Catuvellauni protected them from more powerful or Warlike Tribes, who would otherwise have taken this prime piece of farmland for themselves. When the Romans Invaded Britain in the 43 AD, They gave no resistance to the Romans, and so suffered less losses than the Tribes who fought. I expect that under Roman rule, they just carried on, pretty much as before, Farming the Land, (After all, someone had to do it) but instead of paying a fief to the Catuvellauni, for protection, they traded with the Romans, for imported Luxury goods. They were also one of the only Tribes who used coinage, (a sign that they were rich enough from their farmin