It was, in reality, a plot, under cover of Catholicism, to introduce absolute monarchy, and to make England a dependency of France, not only by the acceptance of French money, but by submission to a French army. Charles I and his ministers had gone to the block for less than this.

If the thing should become known, nobody could foretell the consequences. Turenne was told, because he would be wanted if it came to blows; and Turenne told a lady of his acquaintance, who proved indiscreet. The king, in a fury, asked him how he could be such a fool. The marshal, not unaccustomed to the experience of being under fire, replied that he was not the only man who had been made a fool of by a woman, and King Lewis XIV did not see his way to pursue the conversation. His political object was secured, even if nothing should be done in England to fulfil the agreement. He had Charles completely in his power. The secret text only needed to be divulged, in order to raise the country against him. He never again could be formidable. If all other devices for dividing him from his people were insufficient, this one could not fail. Many years later Lewis caused a book to be printed, by an Italian adventurer, in which the secret was revealed. The book was suppressed and the author imprisoned, for the sake of appearances. But 155 copies were in circulation, and the culprit was released after six days. It became dangerous for Charles to meet parliament. The facts became known to Shaftesbury long before, and determined his course from the time of his dismissal from office, in November 1673. The scheme laid down in the Dover Treaty was a dangerous one, and after the beginning of the Dutch war there were no French troops to spare.

Charles tried another way to gain his purpose. Both he and his brother desired to establish Catholicism for its own sake. They were not converts, but they intended to be before they died. The difference was that James was ready to make some sacrifice for his religion, Charles was not. They both regarded it as the only means of putting the crown above the law. This could be done more safely by claiming the right to dispense from penalties and disabilities imposed by parliament. The idea, entertained as early as 1662, ripened ten years later, when the Penal Laws, as well as the intolerant legislation of Clarendon against the Puritans, which had been considered the safeguard of monarchy, were declared inoperative. The ministers, including Shaftesbury, expected to obtain the support of Nonconformists. This calculation proved delusive. The Dissenters, on an assurance that they would be relieved by parliament if they resisted the offers of the king, refused to accept them. The object of his declaration was too apparent, and was indeed too openly avowed. Just then the Duke of York became a Catholic, and although the fact was not made public, it was suspected. Ministers advised Charles to maintain his offer of indulgence and his claim to the dispensing power. Charles gave way and accepted his defeat. He gave way because Lewis advised it, and promised him more French regiments than had been stipulated for, as soon as he was again at peace with the Dutch.

The House of Commons followed up its victory by passing the Test Act, excluding Catholics from office. The Duke of York resigned his post as Lord High Admiral. It was, he said, the beginning of the scheme for depriving him of the succession to the throne. In November 1673 Shaftesbury, who had promoted the Declaration of Indulgence, was dismissed from office and went into opposition, for the purposes of which Lewis sent him L10,000. He learnt from Arlington the main particulars of the Treaty of Dover, and in the following month of January the secret was substantially made public in a pamphlet, which is reprinted in the State Tracts. From that moment he devoted himself to the exclusion of James.

In 1676 the Duke of York made it known that he had become a Catholic. This was so gratuitous that people took it to mean that he was strong in the support which the French king gave him. He was still true to the policy of the Dover Treaty, which his brother had abandoned, and still watched his opportunity to employ force for the restoration of his Church. All this was fully understood, and his enemy, Shaftesbury, was implacable.

When he had been five years out of office, in September 1678, Titus Oates appeared. Who the people were who brought him forward, with the auxiliary witnesses, Bedloe, Dangerfield, and Turberville, the one who received L600 for his evidence against Stafford, is still unknown. Shaftesbury was not the originator. He would not have waited so many years. His part in the affair was to employ the public alarm for the destruction of the Duke of York. Therefore, from the summer of 1678 there was a second plot. The first, consisting in the Treaty of Dover, drawn up by the Catholic advisers, Arundel, Bellasis, the historian Belling, and Leighton, the great archbishop's brother. The second was the Protestant plot against the Catholics, especially the Duke of York. The indignation against the real plot, that of Dover, was essentially political.

In February 1675 the opposition proposed to James to restore his offices if he would abandon Lewis. When the imperial ambassador, in July 1677, complained of the No Popery cry, they replied that there was no question of religion, but of liberty. In the case of Oates and his comrades, the political motive faded into insignificance beside the religious. At first the evidence was unsubstantial. Oates was an ignorant man, and he obtained credit only by the excitement and distrust caused by the discovery of the premeditated coup d'etat. Godfrey, the magistrate who conducted the inquiry, warned James that the secretary of the Duchess of York, was implicated. His name was Coleman, and he had time to destroy his papers. Some of them were seized. They spoke of a great blow which was being prepared against the Protestants. It appeared also that he was in the pay of Lewis, and had solicited his confessor, Pere La Chaise, for a sum of L300,000 in order to get rid of parliament. It was argued that if such things were found in the papers he had not burnt, there must have been worse still in those which had perished. It showed that the scheme of Dover was still pursued, was still a danger. At that moment the magistrate who sent the warning disappeared. After some days his dead body was found at the foot of Green Berry Hill, now Primrose Hill; and one of the most extraordinary coincidences, so interesting in the study of historical criticism, is the fact that the men hanged for the murder were named Green, Berry, and Hill. It was of course suspected that Godfrey had perished because he knew too much.

For some time the excitement rose very high. On the day when two Jesuits were executed, one of the Catholic envoys writes that nothing else could have saved the lives of all the Catholics in London. Taking advantage of the state of public feeling, Shaftesbury proposed that James should be excluded from the succession for his religion. The crown was to go to the next heir, the Princess of Orange. This was thrown out by the Lords. Meantime the second Test Act expelled the Catholic peers from the House of Lords. James withdrew from the council, from the palace, and at last from the kingdom.

The second Exclusion Bill was founded, not on his religion, but on his politics, that is, his treasonable connection with the King of France. The opponents of exclusion proposed limitation of the royal power, in a manner such as that which has since prevailed. Charles preferred this amendment to the Constitution rather than an Act which enabled parliament to regulate the succession. William of Orange vigorously opposed it, as the same restraints might be retained when his wife came to the throne. Halifax, who defeated the Exclusion Bill and defended the Limitation Bill, assured the prince that it would never be applied, as James had no chance whatever of succeeding his brother. His only purpose in proposing his Bill was to preserve the succession, according to law, from parliamentary control.

In order to obtain evidence that should ruin James's prospects, it was resolved now to put the Catholic peers on their trial. Stafford came first. He had not been in the secret of the fatal Treaty. But the plans this time were cleverly laid. Although Lord Stafford was entirely innocent, Count Thun, the Austrian envoy, was profoundly impressed by the weight of the case against him and the weakness of the defence. He was beheaded amid shrieks of execration and exultation. Arundel was to come next; and Arundel did know enough to compromise the duke. But the plan had failed. Nothing had been discovered in Stafford's trial that could help the exclusion; and a revulsion of popular feeling followed. Monmouth was now put forward. If James could not be excluded he must make way for Monmouth, if Monmouth was legitimate. The king was pressed to acknowledge him. A black box was said to contain the necessary evidence of his mother's marriage. A bishop was spoken of who knew all about it. Monmouth himself accepted the idea. When the Duke of Plymouth died he refused to wear mourning. He would not mourn, he said, for a brother who was illegitimate. After the Test Act, the Exclusion Bill, the succession of Monmouth, the indefatigable Shaftesbury had still one resource. He tried an insurrection. When he found it impossible to draw the line between insurrection and murder, he thought the position dangerous, and went abroad. Russell and Sidney were put to death. Charles was victorious over his enemies. He owed his victory to the French king, who gave him L700,000, and enabled him to exist without a parliament for three years.