This strict union of the three large states became a potent bulwark for their security, and made them, in more than one century, the arbiter of the European system; the three nations of the northern peninsula presenting a compact and united front, that could bid defiance to any foreign aggression.
Although Eric of Pomerania was elected king, and in 1407 passed his minority, Margaret continued governing until the day of her death. "You have done all well," wrote the people to her, "and we value your services so highly that we would gladly grant you everything." The union of the three Scandinavian kingdoms having been established in Calmar, all her efforts were now aimed at regaining the duchy of Schleswig, which circumstances had compelled her to resign to Gerhard IV, Count of Holstein. For such a reunion with Schleswig a favorable opportunity appeared, when Gerhard was killed in an expedition against the Ditmarshers, leaving behind three sons in minority. Elizabeth, Gerhard's widow, fled to Margaret for succor against her violent brother-in-law, Bishop Henry of Osnabrueck. Margaret, fond of fishing in foul water, was very willing to help her, but availed herself of the opportunity to annex successively different parts of Schleswig.
The dethroned Swedish King, Albert, never able to forget his anger toward Margaret or her severity against him, and continually cherishing a hope of reascending the Swedish throne, and considering the Union of Calmar a breach of peace, contrived to make the Swedish people displeased with her, and thought it a suitable time to revolt from her dominion. He established a strong camp before Visby, the capital of the island of Gulland, having six thousand foot and, at some distance, nine thousand horse. Determined to engage before their junction could take place, the Queen's commander-in-chief, Abraham Broder, immediately advanced until in sight of the enemy, and then endeavored to gain possession of Visby and the ground near by. In this he was so far successful that Albert and his army had to leave the camp and conclude a truce. But nevertheless he did not till after a lapse of seven years give up his hope of remounting the throne of Sweden, making a final peace with Margaret, and henceforward living in Gadebush, Mecklenburg, where in 1412 he closed his inglorious life.
Soon after, October 27th, Queen Margaret died on board a ship in the harbor of Flensburg, at the age of fifty-nine, after an active and notable reign of thirty-seven years. Her funeral was attended with the greatest solemnity, and her corpse was brought to the Cathedral of Roeskilde, where Eric of Pomerania, her successor, in 1423, caused her likeness to be carved in alabaster. Her acts show her character. She displayed judiciousness united with circumspection; wisdom in devising plans, and perseverance in executing them; skill in gaining the confidence of the clergy and peasantry, and thereby counterbalancing the imperious nobility. On the whole she applied herself to the civilization of her three kingdoms, and to their improvement by excellent laws, the great aim of which was to undermine the nobility. She pursued the plan of her great father to recall all rights to the crown lands, which during the reign of her weak and inefficient predecessors had been granted to the nobility. The prosecution of this plan for the perfect subversion of the feudal aristocracy was unfortunately interrupted by her death; her imprudent and weak successor having no power to restrain the turbulent spirit of a factious nobility.