Principles such as these were intolerable to James. By the law of England the king was head of the Church; and it was, therefore, his policy to introduce an uniformity of ecclesiastical government over the whole island. For more than twenty years before the Union of the Crowns he had been engaged in fighting the Scottish clergy. Sometimes he won, and sometimes he was defeated. The great point at issue was whether the Scottish Church was to be Presbyterian or Episcopal; for he had found that if the Presbyterian system was allowed to exist, the royal supremacy would never be acknowledged in Scotland. Accordingly he came to the throne of England with a firm resolution that he would use his new position so as to secure the establishment of Episcopacy in the north; and, though he artfully concealed it, we may be sure that one of his chief reasons for proposing the Union was that he believed it would be followed by the accomplishment of this object. Henceforth the policy of extending the Anglican system to Scotland became the hereditary policy of the Stuarts. Three years after the Union of the Crowns, the boldest leaders of the clergy having been driven into exile, the Scottish Parliament acknowledged the royal supremacy over all persons and all causes. It was not long before Episcopacy was established; and James had the gratification of seeing a few of his new bishops humbly consenting to receive consecration from the hands of English prelates, and returning to Scotland to confer upon their brethren the virtues of the apostolical succession. But the system which was thus set up had no hold upon the people. It would be impossible to point out in the catalogue of Scottish bishops the names of a dozen men who were either popular, or famous for learning, or eminent on account of their public services. The history of Christendom contains no story so humiliating as the story of Prelacy in Scotland during the seventeenth century.