Louis the Fat took the field in person against him.

"Men-at-arms, and in very small numbers, too," says Guibert of Nogent, "were with difficulty induced to second the king, and did not do so heartily; but the light-armed infantry made up a considerable force, and the Archbishop of Rheims and the bishops had summoned all the people to this expedition, whilst offering to all absolution from their sins.

Thomas de Marle, though at that time helpless and stretched upon his bed, was not sparing of scoffs and insults towards his assailants; and at first he absolutely refused to listen to the king's summons." But Louis persisted without wavering in his enterprise, exposing himself freely, and in person leading his infantry to the attack when the men-at-arms did not come on or bore themselves slackly.

He carried successively the castles of Crecy and Nogent, domains belonging to Thomas de Marle, and at last reduced him to the necessity of buying himself off at a heavy ransom, indemnifying the churches he had spoiled, giving guarantees for future behavior, and earnestly praying for re-admission to the communion of the faithful.

As for those folks of Laon, perpetrators of or accomplices in the murder of Bishop Gaudri, who had sought refuge with Thomas de Marle, the king showed them no mercy.