The duke had left Calais garrisoned by a strong force, under Marshal Termes. He had since ordered that veteran to take command of a body of fifteen hundred horse and five thousand foot, drawn partly from the garrison itself, and to march into West Flanders. Guise proposed to join him there with his own troops, when they would furnish such occupation to the Spaniards as would effectually prevent them from a second invasion of Picardy. The plan was well designed, and the marshal faithfully executed his part of it. Taking the road by St. Omer, he entered Flanders in the neighborhood of Dunkirk, laid siege to that flourishing town, stormed and gave it up to pillage. He then penetrated as far as Nieuport, when the fatigue and the great heat of the weather brought on an attack of gout, which entirely disabled him. The officer on whom the command devolved allowed the men to spread themselves over the country, where they perpetrated such acts of rapacity and violence as were not sanctioned even by the code of that unscrupulous age. The wretched inhabitants, driven from their homes, called loudly on Count Egmont, their governor, to protect them. The duke of Savoy lay with his army, at this time, at Maubeuge, in the province of Namur; but he sent orders to Egmont to muster such forces as he could raise in the neighboring country, and to intercept the retreat of the French, until the duke could come to his support and chastise the enemy. Egmont, indignant at the wrongs of his countrymen, and burning with the desire of revenge, showed the greatest alacrity in obeying these orders. Volunteers came in from all sides, and he soon found himself at the head of an army consisting of ten or twelve thousand foot and two thousand horse. With these he crossed the borders at once, and sent forward a detachment to occupy the great road by which De Termes had penetrated into Flanders. The French commander, advised too late of these movements, saw that it was necessary to abandon at once his present quarters, and secure, if possible, his retreat. Guise was at a distance, occupied with the troubles of his own camp. The Flemings had possession of the route by which the marshal had entered the country. One other lay open to him along the sea-shore, in the neighborhood of Gravelines, where the Aa pours its waters into the ocean. By taking advantage of the ebb, the river might be forded, and a direct road to Calais would be presented. Termes saw that no time was to be lost. He caused himself to be removed from his sick-bed to a litter, and began his retreat at once. On leaving Dunkirk, he fired the town, where the houses were all that remained to the wretched inhabitants of their property. His march was impeded by his artillery, by his baggage, and especially by the booty which he was conveying back from the plundered provinces. He however succeeded in crossing the Aa at low water, and gained the sands on the opposite side. But the enemy was there before him.[234]