The critical years of William's conquest of England had been undisturbed by any dangers threatening his continental possessions. Matilda, who spent most of the time in Normandy, with her councillors, had maintained peace and order with little difficulty; but in the year after his Scottish expedition he was called to Normandy by a revolt in his early conquest, the county of Maine, which it required a formidable campaign to subdue. William's plan to attach this important province to Normandy by a marriage between his son Robert and the youngest sister of the last count had failed through the death of the proposed heiress, and the county had risen in favour of her elder sister, the wife of the Italian Marquis Azo or of her son. Then a successful communal revolution had occurred in the city of Le Mans, anticipating an age of rebellion against the feudal powers, and the effort of the commune to bring the whole county into alliance with itself, though nearly successful for the moment at least, had really prepared the way for the restoration of the Norman power by dividing the party opposed to it. William crossed to Normandy in 1073, leading a considerable army composed in part of English. The campaign was a short one. Revolt was punished, as William sometimes punished it, by barbarously devastating the country. Le Mans did not venture to stand a siege, but surrendered on William's sworn promise to respect its ancient liberty. By a later treaty with Fulk of Anjou, Robert was recognized as Count of Maine, but as a vassal of Anjou and not of Normandy.