When Hans was made king of Denmark his ambitious brother Frederick, who had sought to obtain the throne, was made duke of Sleswick-Holstein, and called upon the Ditmarshers to pay him taxes and render homage to him for their lands. This they declined to do, not recognizing the right of the Emperor Frederick to hand them over to Denmark and to decide that the country which had belonged to their fathers for so many centuries was part of Holstein. Finding that he had tough metal to deal with in the brave marshmen, Frederick induced his brother Hans to invade their country and seek to bring them to terms. King Valdemar had done the same thing three centuries before, with the result of losing four thousand men and getting an arrow wound in his eye, but undeterred by this, if they knew anything about it, the nobles and knights, who were very numerous in the army led by Frederick and Hans, went to the war as lightly as if it were an excursion of pleasure. Disdaining to wear their ordinary armor in dealing with peasant foes, they sought to show their contempt for such an enemy by going in their ordinary hunting costume and carrying only light arms. It was a piece of folly, as they were to learn. The marshmen fought like their fathers of old for their much-valued liberty, and the knights found they had no cravens to deal with. It is true that the royal troops took and sacked Meldorf, the chief town of the Ditmarshers, cruelly killing its inhabitants, but it was their only victory. It proved a lighter thing to get to Meldorf than to get away from it, and of the Danes and Germans who had taken part in the assault few escaped with their lives. It was the depth of winter, cold, bitter weather, and as the army was on its march from Meldorf to Hejde the advance guard suddenly found itself in face of a line of earthworks which the marshmen had thrown up in front of a dike. This was defended by five hundred Ditmarshers under their leader, Wolf Isebrand. The German guards rushed to the attack, shouting: "Back, churls, the guards are coming!" Three times they forced the marshmen to retreat, but as often these bold fellows rallied and came back to their works. In the midst of the struggle the wind changed, bringing a thaw with it, and as the troops struggled on, blinded with the sleet and snow that now fell heavily, and benumbed with the cold, the men of the marshes opened the sluices in the dike. Through the openings poured the waters of the rising tide, quickly flooding the marshes and sweeping everything before them. The soldiers soon found themselves wading in mud and water, and at this critical juncture the Ditmarshers, accustomed to make their way through their watery habitat by the aid of poles and stilts, fell upon the dismayed invaders, cutting them down in their helpless dilemma or piercing them through with their long lances.