In the 1550s, King Gustav Vasa of Sweden found that the Danish King Christian III had added the three crowns to his own coat of arms. Because the three crowns had been a Swedish symbol since the 14th century and were used by Danish monarchs only during the Kalmar Union, Gustav interpreted Christian III's use of the symbol as a sign of intent to conquer Sweden and resurrect the union. Christian countered that since the monarchs of the union had used the three crowns, the symbol now belonged to both kingdoms and thus he had as much a right as the Swedish king to use it.