Tony Bradman 
Revolt Against the Romans [PDF ebook] 

‘I”ve fought every kind of barbarian, but the Britons are by far the worst…’
Marcus is excited about travelling to Britannia, the island at the edge of the world. But the Britons are savages who tattoo themselves and take the heads of their enemies in battle. They won”t bow down to the rule of Rome.
As Marcus travels to meet his father he meets a barbarian chief instead and his destiny is changed forever, along with that of Britannia…