First published in 1882, this clearly written account, accessible to non-specialists, is one of the principal works of the pioneering Celtic scholar Sir John Rhys (1840–1915). The son of a Welsh farmer and lead miner, Rhys went on to become the first professor of Celtic at the University of Oxford, principal of Jesus College, and a fellow of the British Academy. Knighted in 1907, Rhys had by then made significant contributions to the study of Celtic languages, travelling widely and examining many inscriptions at first hand. Here he covers Celtic etymology, ethnology and history in Britain from the time of Julius Caesar to the eleventh-century Scottish kingdoms. His Lectures on Welsh Philology (1877) and Celtic Folklore: Welsh and Manx (1901) are also reissued in the Cambridge Library Collection. For the study of Celtic language, culture and mythology, the importance of Rhys's research is still acknowledged today.