The Emperor was soon convinced that his mediation must fail, and that France was resolved to renew the war. He then determined not to remain neutral, but to join himself by a solemn league with Henry. The preamble of this covenant is deeply interesting, as indicative, at least, of the professed sentiments of Sigismund with regard to the pretensions of Henry, and to the conduct and character of the two belligerent kings. Sigismund declared the object of his desire to have been the restoration of peace to the church and to Christendom; and, with that end in view, he had endeavoured to reconcile the Kings of England and France, but without success. The failure he ascribed entirely to the hatred of peace which influenced the French King, to whom he attributed also the prevalence of schism in the church, and the disturbed state of the Christian world. He then expresses his resolution "to form a league with Henry in the name of the Lord God of Hosts, and to assist him in the recovery of his JUST RIGHTS."[158] This league was signed August 15, 1416. The Emperor, shortly after (p. 209) this unlooked-for termination of his office as mediator, left England. Before he had proceeded onwards from Calais, Henry himself arrived at that town. After some days, the Duke of Burgundy also joined them; and much time was spent in secret negociations, the nature of which did not transpire, though we may suppose both the Emperor and King were anxious to make him a party to the league already concluded between themselves. A covenant, however, was signed by the Duke early in October, in which he declared that, "though he had taken part with the enemies of Henry in time past, yet now, _being assured of his lawful claim_, he would employ his arms in his service as the rightful King of France." [Footnote 158: Rymer, H. V. An. iv.]