The Emperor met the advances of Henry with promptitude, which showed the importance he attached to the alliance. Reginald of Cologne was sent to England to propose a double alliance with the house of Swabia, of Frederick's son, and of Henry the Lion, with the two daughters of Henry Plantagenet. The Pope trembled at this threatened union between the houses of Swabia and England. At the great diet held at Wurtzburg, Frederick, asserted the canonical election of Paschal III., the new Antipope, and declared in the face of the empire and of all Christendom, that the powerful kingdom of England had now embraced his cause, and that the King of France stood alone in his support of Alexander.[92] In his public edict he declared to all Christendom that the oath of fidelity to Paschal, of denial of all future allegiance to Alexander, administered to all the great princes and prelates of the empire, had been taken by the ambassadors of King Henry, Richard of Ilchester, and John of Oxford.[93] Nor was this all. A solemn oath of abjuration of Pope Alexander was enacted, and to some extent enforced; it was to be taken by every male under twelve years old throughout the realm.[94] The King's officers compelled this act of obedience to the King, in villages, in castles, in cities. If the ambassadors of Henry at Wurtzburg had full powers to transfer the allegiance of the King to the Antipope; if they took the oath unconditionally, and with no reserve in case Alexander should abandon the cause of Becket; if this oath of abjuration in England was generally administered; it is clear that Henry soon changed, or wavered at least in his policy. The alliance between the two houses came to nothing. Yet even after this he addressed another letter to Reginald, Archbishop of Cologne, declaring again his long cherished determination to abandon the cause of Alexander, the supporter of his enemy, the Archbishop of Canterbury. He demanded safe-conduct for an embassy to Rome, the Archbishop of York, the Bishop of London, John of Oxford, De Luci, the Justiciary, peremptorily to require the Pope to annul all the acts of Thomas, and to command the observance of the Customs.[95] The success of Alexander in Italy, aversion in England to the abjuration of Alexander, some unaccounted jealousy with the Emperor, irresolution in Henry, which was part of his impetuous character, may have wrought this change. The monk and severe student of Pontigny found rest neither in his austerities nor his studies.[96] The causes of this enforced repose are manifest--the negotiations between Henry and the Emperor, the uncertainty of the success of the Pope on his return to Italy. It would have been perilous policy, either for him to risk, or for the Pope not to inhibit any rash measure. [SN: Becket cites the King.]