The Battle of Bornholm (1563) was the naval battle that would eventually lead to the outbreak of the Northern Seven Years' War
Background
In early 1563, 20 years after the Dacke War, the Swedish admiral Jakob Bagge was a 60 year old veteran. Eric XIV ordered him to provoke the Danes near Gotland or Bornholm and get them to attack the Swedish fleet, so that war on Denmark could be declared on the pretext of self-defense. For this reason, Bagge ordered the crew on the Swedish ships not to strike the top sail on their ships which was a normal practice to show respect.
Bagge hoped this would be insulting enough for the Danes to attack. If events would proceed like Eric had planned, all of Europe would hear how Danish ships attacked the "poor Swedish ships who were just on the way to transport a wife for their king" The Swedes did not spare any of their gunpowder, the hole in the Elefanten's sail was compensated for in the ensuing battle, which lasted several hours. Almost immediately, a Swedish cannonball hit the mainmast of the Herkules, which fell down and landed in the middle of the firing line for the men onboard, while the Danes were removing the mast, the Swedes continued shooting at the ship, causing heavy casualties. The Danes, who were aware of the possibility that fighting would break out, were taken by surprise by the Swedes.