Chester 615
Category: Dark Age Battles
Aethelfrith of Northumbria, which extended to the Isle of Man at that time, surprised and defeated two Welsh princelings with a swift approach march, and allegedly killed 1200 monks from Bangor in the process! - these may have been Celtic warrior monks. Arthur may also have fought against the Saxons at Chester, though this was perhaps more likely at Caerleon in south Wales.