A dozen contented years he reigned in peace, doing justice between man and man at home.  Then the curse of his house gripped him.  In two centuries, since the brief union between the three Scandinavian kingdoms was broken by the secession of Sweden, only two of sixteen kings in either country had gone to their rest without ripping up the old feud.  It was now Christian’s turn.  The pretext was of little account:  there was always cause enough.  Gustav Adolf, whose father was then on the throne of Sweden, said in after years that there was no one he had such hearty admiration for and whose friend he would like so well to be as Christian IV:  “The mischief is that we are neighbors.”  King Christian crossed over into Sweden and laid siege to the strong fortress of Kalmar where he first saw actual war and showed himself a doughty campaigner of intrepid courage.  It came near costing him his life when a cannoneer with whom he had often talked on his rounds deserted to the enemy and picked the King out as his especial target.  Twice he killed an officer attending upon him, but the King he never hit.  It is almost a pleasure to record that when he tried it again, in another fight, Christian caught him and dealt with him as the traitor he was, though the rough justice of those days is not pleasant to dwell on.  The besieged tried to create a diversion by sneaking into camp at night and burying wax images of the King and his generals in the earth, where they were afterwards found and spread consternation through the army; for such things were believed to be wrought by witchcraft and to bring bad luck to those whom they represented.

However, neither the real courage of the defenders, nor their dallying with the black art, helped them any.  King Christian stormed the town at the head of his army and took it.  The burgomaster hid in the church, disguised as a priest, and pretended to be shriving some women when the crash came, but it did not save him.  When the Swedish king came with a host twice the size of his own, there was a battle royal, but Christian drove him off and laid siege to the castle where dissension presently arose between the garrison and its commander who was for surrendering.  In the midst of their noisy quarrel, King Christian was discovered standing upon the wall, calmly looking on.  He had climbed up alone on a rope ladder which the sentinel let down at his bidding.  At the sight they gave it up and opened the gates, and the King wrote home, proudly dating his letter from “our castle Kalmar.”

Its loss so angered the Swedish king who was old and sick, that he challenged Christian to single combat, without armor.  The letters that passed between them were hardly kingly.  King Christian wrote that he had other things to do:  “Better catch a doctor, old man, and have your head-piece looked after.”  Helpless anger killed Karl, and Gustav Adolf, of whom the world was presently to hear, took the command and the crown.  After that Christian had a harder road to hoe.