But while the nation grumbled and the Parliament remonstrated, one party in the realm was filled with absolute panic by the news of the Spanish match. The Protestants saw in the marriage not only the final overthrow of their religious hopes, but a close of the religious truce, and an opening of persecution. The general opposition to the match, with the dread of the holders of Church lands that their possessions were in danger, encouraged the more violent to plan a rising; and France, naturally jealous of an increase of power by its great opponent, promised to support them by an incursion from Scotland and an attack on Calais. The real aim of the rebellion was, no doubt, the displacement of Mary, and the setting either of Jane Grey, or, as the bulk of the Protestants desired, of Elizabeth, on the throne. But these hopes were cautiously hidden; and the conspirators declared their aim to be that of freeing the Queen from evil counsellors, and of preventing her union with the Prince of Spain. The plan combined three simultaneous outbreaks of revolt. Sir Peter Carew engaged to raise the west, the Duke of Suffolk to call the midland counties to arms, while Sir Thomas Wyatt led the Kentishmen on London. The rising was planned for the spring of 1554. But the vigilance of the Government drove it to a premature explosion in January, and baffled it in the centre and the west. Carew fled to France; Suffolk, who appeared in arms at Leicester, found small response from the people, and was soon sent prisoner to the Tower. The Kentish rising however proved a more formidable danger. A cry that the Spaniards were coming "to conquer the realm" drew thousands to Wyatt's standard. The ships in the Thames submitted to be seized by the insurgents. A party of the train-bands of London, who marched with the royal guard under the old Duke of Norfolk against them, deserted to the rebels in a mass with shouts of "A Wyatt! a Wyatt! we are all Englishmen!"
Had the Kentishmen moved quickly on the capital, its gates would have been flung open and success would have been assured. But at the critical moment Mary was saved by her queenly courage. Riding boldly to the Guildhall she appealed with "a man's voice" to the loyalty of the citizens, and denounced the declaration of Wyatt's followers as "a Spanish cloak to cover their purpose against our religion." She pledged herself, "on the word of a Queen, that if it shall not probably appear to all the nobility and commons in the high court of Parliament that this marriage shall be for the high benefit and commodity of all the whole realm, then will I abstain from marriage while I live." The pledge was a momentous one, for it owned the very claim of the two Houses which the Queen had till now haughtily rejected; and with the remonstrance of the Parliament still fresh in their ears the Londoners may well have believed that the marriage-project would come quietly to an end. The dread too of any change in religion by the return of the violent Protestantism of Edward's day could hardly fail to win Mary support among the citizens. The mayor answered for their loyalty, and when Wyatt appeared on the Southwark bank the bridge was secured against him. But the rebel leader knew that the issue of the revolt hung on the question which side London would take, and that a large part of the Londoners favoured his cause. Marching therefore up the Thames he seized a bridge at Kingston, threw his force across the river, and turned rapidly back on the capital. But a night march along miry roads wearied and disorganized his men; the bulk of them were cut off from their leader by a royal force which had gathered in the fields at what is now Hyde Park Corner, and only Wyatt himself with a handful of followers pushed desperately on past the palace of St. James, whence the Queen refused to fly even while the rebels were marching beneath its walls, along the Strand to Ludgate. "I have kept touch," he cried as he sank exhausted at the gate. But it was closed: his adherents within were powerless to effect their promised diversion in his favour; and as he fell back the daring leader was surrounded at Temple Bar and sent to the Tower.