He did not intend to keep his word, but was no sooner set free than he sought aid from his brother-in-law, the king of Denmark, and invaded the kingdom with a Danish army. This was the third war above spoken of. It ended without the king gaining anything but the third of the kingdom, which had already been promised to him. After each of these wars the brothers became reconciled, and lived for a time peacefully in their dominions, but they laid such heavy taxes on the people to support their extravagant courts that great misery prevailed.
After the last outbreak all remained quiet for nearly ten years, and the dukes thought that their brother was friendly towards them, not dreaming that his heart was full of hate and treachery.
In 1317, when Duke Valdemar made a journey to Stockholm, which was in his section of the kingdom, he stopped at Nyköping to visit his brother Birger, whom he had not seen for a long time. Birger met him with a great show of friendliness, making him welcome in every way. Queen Martha was equally kind, and Valdemar was highly pleased with these tokens of regard. Before he left the queen complained to him that it gave her great pain that Duke Erik avoided his brother, saying that God knew she loved him as much as if he were her own brother.
After spending the night with them Valdemar rode away very well pleased. His men were equally pleased, for they had been well entertained. On leaving Stockholm he went to Erik's home in Westmoreland, who told him that he had just been invited to visit Birger's court, and asked if he thought it safe to make such a visit.
Valdemar said he had no doubt of it, telling of what a pleasant visit he had made. Erik, however, had doubts, being distrustful of the queen and Chancellor Brunke, whom he looked upon as his enemies. But in the end the brothers decided to accept the invitation and rode away towards Nyköping. When six miles distant they met a knight who advised them to go no farther, saying:
"You will cause yourselves and your friends much sorrow if both of you trust yourselves in the king's hands at the same time."
Valdemar indignantly replied to this that "there are too many who seek to breed disunion between the king and his brothers."
The knight then rode off, saying no more, and the dukes rode into Swärta, where they proposed to spend the night. To their surprise no preparations had been made for them, but a knight met them and saluted them in the king's name, adding that he earnestly requested them not to repose until they reached Nyköping, as his longing to meet them was so great that he could not rest until they arrived.
On receiving this warm request they rode on, reaching Nyköping in the evening. The king advanced from the castle gate to meet them, greeting them in an affectionate manner, and taking each of them by the hands as he led them into the castle. They found a rich feast prepared for them, at which neither mead, wine, nor fair words were wanting. At length Duke Valdemar grew suspicious and said to his brother that they were drinking too much wine. But this was soon forgotten and the feast went on, Queen Martha showing herself very gay and lively and every one being full of the spirit of enjoyment.
It was late at night before the merrymaking ended and the dukes went to their rooms. The queen then said to their men, who had also been well taken care of: