In order however that the Church might exert this unifying influence on English politics it was essential that she should be of one mind herself; but at this time the unfortunate division between the Roman and the Celtic Churches on the utterly unimportant questions of the shape of the tonsure and the right calculation of Easter did much to prevent so desirable a consummation. Utterly unimportant they seem to us, and probably few ecclesiastics of any school of thought would now deny their triviality; but there is a well-known law of theological dynamics that the bitterness of feeling between rival Churches is in inverse proportion to the magnitude of the issues between them; and so it proved at this crisis. Owing to the different quarters from which the different English kingdoms had received their Christianity, the religious map of England was divided in the following manner. Kent and East Anglia were firm in their following of Rome. Wessex also, which had been won for Christianity by Birinus, was steadily, though perhaps not enthusiastically, Roman. Bernicia, till late in the reign of Oswy, clung firmly to the teachings of Iona. Deira seems to have been generally on the same side, though the remembrance of the teaching of Paulinus, kept alive, as it was, by the teaching of his follower James the Deacon, had probably modified the strength of its Celticism; and Alchfrid the king, influenced by the persuasions of his friend Cenwalh, King of Wessex, had embraced with fervour the party of Rome. Mercia and Essex, both of which had been evangelised by Northumbrian missionaries, seem to have been somewhat half-hearted in their adherence to the Celtic traditions.