The Treaty of Dover
From 'A History of the British Nation' by AD Innes, 1912
[In the reign of Charles II] The time was coming, though it had not yet come, when Catholic and Protestant Powers would have to unite against the aggression of France, revealed as the open enemy of toleration. The position was not as yet generally grasped in England; but England was uneasy and restive on political more than on religious grounds. Louis had recently put forward a claim to provinces of the Spanish Netherlands on behalf of his wife, who was the elder sister of the infant King of Spain, the basis of the claim being certain local customs of succession which could not in the eyes of any one except Louis apply to the sovereignty. England was feeling extremely suspicious of Louis's ambitions.
The Triple Alliance
Hence Charles found himself constrained to give open assent to the formation, through the diplomatic agency of Sir William Temple, of the Triple Alliance between England, Holland, and Sweden, with the ostensible object of inducing France and Spain to come to terms.
That object was accomplished, since Louis was not at this stage prepared to defy such a coalition. But Charles had been careful to explain privately to his cousin that he was not a free agent in the matter. The Triple Alliance must be looked upon merely as a temporary check.
The Treaty of Dover
The two kings entered on a course of secret negotiations which resulted in the most shameful compact in our annals. By the secret Treaty of Dover, of which the true details remained unknown until revealed by modern research, Charles undertook to join Louis in a war against Holland. In return for his alliance Charles was to receive substantial subsidies from the French king. This portion of the compact was confirmed by a treaty made in the following year to which all the members of the Cabal were privy; but the iniquity of the secret treaty lay in clauses which were concealed from Ashley and Buckingham.
Charles pledged himself to reinstate the Roman Catholic religion and himself to join the Roman communion, as his brother James had already done, as well as Clifford. And the price of this pledge was the promise of a substantial pension, a sum down when the king's conversion should be publicly announced, and a guarantee that Charles should be supported by French troops if his subjects revolted.
Charles himself and all the members of the Cabal were advocates of toleration, though for different reasons. For the principle of toleration Charles cared nothing; he had no sympathy with Puritanism or the puritans. But he and Clifford and Arlington were shrewd enough to perceive that it was hardly possible to seek for a relaxation of the laws against Roman Catholics without also relaxing those against Protestant dissent. Ashley and Buckingham, on the other hand, were allied to the dissenters.
But the Cavalier parliament was hotly intolerant alike of Romanism and of Nonconformist Puritanism. Buckingham and, what was infinitely more important, Ashley were both duped by Charles, and, knowing nothing of the secret treaty, favoured the French alliance against the Dutch; relying upon the commercial advantages which would accrue and upon the sentiment of hostility to Holland, the desire to avenge the disgrace of the Medway affair, to make a Dutch war popular.