It was evident to all that the position of Cromwell at court had become very insecure. While England was threatened with an European coalition he had suggested an alliance with the Protestant princes of Germany， and as Henry's third wife Jane Seymour had died (1537)， after having given birth to a son (later on Edward VI.)， he determined to cement the bond of friendship by a new matrimonial alliance. The Duke of Cleves was brother-in-law to the Elector of Saxony and one of the guiding spirits of the Schmalkaldic League， and as he had given mortal offence to the Emperor by his acceptance of the Duchy of Guelders， Cromwell decided that a marriage between the Duke's sister， Anne， and Henry VIII. would secure for England both the alliance of the League of Schmalkald and at least the neutrality of France. Though Henry detested the Elector of Saxony and his friends as heretics， and though the Six Articles aroused considerable resentment in the Lutheran camp， the close union between Charles V. and Francis I. and the uncertainty of what steps they might take made it imperative to push forward Henry's marriage. The marriage treaty was signed in October 1539， and in December Anne of Cleves landed at Deal. Henry， who had been led to believe that Anne was both accomplished and moderately beautiful， could not conceal his disappointment when he met his prospective bride； but， as his trusted counsellors could devise no plan of escape， he consented with bad grace to go through the ceremony of marriage (6th Jan.， 1540). Henry was displeased and made no secret of his displeasure. Cromwell， whom he blamed specially for this matrimonial misfortune， felt himself in considerable danger， though at the same time he resolved not to yield without a struggle. The contest between Cranmer， backed by the Lutheran party in the council， and Gardiner， the Duke of Norfolk， and the conservatives was sharp though by no means decisive. The king appeared at one time to favour one side， at another the other side， unwilling to commit himself definitely to either， especially as Cromwell was still reaping a rich harvest from the suppression of the Knights of St. John and from the taxes imposed on the clergy.
Parliament met again in April 1540. To the surprise of many Cromwell was created Earl of Essex (17th April)， while a little later Bishop Sampson was arrested as a supporter of the Pope. The hopes of Cromwell and of the reforming party rose rapidly， and they believed that victory was within their grasp. The committee of bishops was at work considering the sacraments， but as both the old and the new clung tenaciously to their opinions no progress could be made. Suddenly on the 10th June an officer appeared in the council chamber and placed Cromwell under arrest. The long struggle was at last ended， and the men who had followed Gardiner had won the day. The war clouds， that had driven Henry to negotiate with the heretical princes of Germany， had blown over， and Cromwell， who had taken a leading part in the German negotiations， must be sacrificed to satisfy his enemies at home and Catholic opinion on the Continent. He was committed to the Tower to await the sentence of death which he knew to be inevitable， but， before handing him over to the executioner， Henry insisted that he should perform for him one last service. As Cromwell had involved him in an undesirable marriage with Anne of Cleves， he should provide evidence that might set his master free to seek for a more congenial partner. At the command of the king Cromwell wrote a long letter， in which he showed that Henry never really consented to the marriage with Anne， against which marriage the existence of a pre-nuptial contract was also adduced. On the strength of this， Parliament demanded an investigation， and a commission was issued empowering the Archbishops of Canterbury and York and others of the clergy to examine into the validity of the marriage. Convocation decided that it was null and void (July 1540)， a decision with which Anne expressed her complete satisfaction. She was assigned a residence and a pension of ā4，000 a year. On the 28th July， 1540， Cromwell was led to execution at Tyburn， where he expressed publicly his adherence to the ancient faith， for the destruction of which in England he had contributed more than any single individual with the exception possibly of the king.[43] A few days later Henry was married to Catharine Howard， a niece of the Duke of Norfolk， the recognised lay head of the conservative party in England.