It was not until 1437 that serious trouble began at Bruges. Its ostensible cause was the old dispute anent her jurisdiction over Sluys, but in reality it was the outcome of the people's discontent at Philippe's centralizing policy, and at the ignoble means by which he pursued it; by stirring up strife betwixt class and class, and town and town, and man and man; by corrupting magistrates, in order that they might lend themselves to the falsification of money, and the increase of taxation; by undermining the authority of city officers by modifying the basis on which it reposed, and by exciting the lower classes against them. The treaty of Arras, by which Philippe concluded, on July 1, 1435, a formal alliance with France, was profoundly unpopular with the Flemish burghers, and the war with England, in which it involved them, was still less to their liking. They knew very well that it was not to their interest to quarrel with their former ally, and if in those days there had been in England an Edward III., or an Artevelde in Flanders, they would have had no hesitation in joining hands with the English against the tyrant who was oppressing them, as they had done in the days of Louis of Maele. As it was, it needed all Philippe's tact and sophistry, and no inconsiderable expenditure of cash in bribes, to induce them to render him assistance, and perhaps even then there was some secret understanding with the enemy. The force which the burghers had given him only remained under arms some two months, from June 11 to August 26, (1436). When the Burgundian fleet under De Horne fled before the English admiral, a great cry went up from the Flemings encamped before Calais--_'Go, go wy zyn all vermanden_,' and they forthwith packed up their traps, staved in the casks of wine that they were unable to carry with them and returned to their homes.