The war began in 1111, and the danger was great enough to call Henry himself over sea in August and keep him on the continent for nearly two years. The leading part was taken by the count of Anjou, whose marriage enabled him to add the famous “Cenomannian swords” to the forces of Touraine and the Angevin March.[568] Moreover, treason was, as usual, rife among the Norman barons; and the worst of all the traitors was Robert of Bellême. One after another the lesser offenders were brought to justice; at last, in November 1112, Robert himself fell into the hands of his outraged sovereign, and, to the joy of all men on both sides of the sea, was flung into a lifelong captivity.[569] Then at last Henry felt secure in Normandy; the capture of Robert was followed by the surrender of his fortress of Alençon, and the tide of fortune turned so rapidly that Fulk and Louis were soon compelled to sue for peace. Early in Lent 1113 Fulk and Henry met at Pierre-Pécoulée near Alençon; the count submitted to perform the required homage for Maine, and his infant daughter was betrothed to Henry’s son, the little Ætheling William. In March the treaty was confirmed by the two kings at Gisors; and as the first-fruits of their new alliance there was seen the strange spectacle of a count of Anjou and a count of Blois fighting side by side to help the lord of Normandy in subduing the rebels who still held out in the castle of Bellême.[570] [568] Eng. Chron. a. 1111, 1112. [569] Eng. Chron. a. 1112. Ord. Vit. (as above), pp. 841, 858. Will. Malm. _Gesta Reg._, l. v. c. 398 (Hardy, p. 626). [570] Ord. Vit. (Duchesne, _Hist. Norm. Scriptt._), p. 841.