G. A. Henty 
Beric the Briton 

A fantastic historical novel by British author G. A. Henty, viewing the Roman invasion of Britain through the eyes of Beric, a Briton who, under Queen Boudica, rises up against the Roman oppressors. He then goes on to have many adventures, including fighting in Rome’s arena as a gladiator, and becoming a guard of Emperor Nero.