Bring up a cannon, restore it, mount it on Kalmar's walls, and fire it every year on the anniversary of the battle out over the Baltic toward's Denmark.

The wreck of the 16th century Swedish warship Mars, flagship of King Eric XIV (r. 1560-1568), son of Gustavus Vasa, first of his dynasty and first king of an independent Sweden, has been digitally captured in defiance of awful visibility conditions at the bottom of the Baltic in a combination of actual footage and 3D rendering.

 In 1561, King Eric of Sweden engaged master shipwright Holgerd Olsson to build the biggest ship yet. It was Eric’s idea to call it the Mars after the Roman god of war, telegraphing even more clearly his bellicose intent. Mars was completed in the fall of 1563.  Also known as the Makalös (Matchless), the ship was big, the largest ever up until that point on the Baltic. It was said to be longer than Eric's rival Lübeck’s cathedral of St. Peter.

Anyone who has seen the massive Vasa in Stockholm, which the Swedes dragged up from the bottom of the sea and restored, can appreciate the nearly unbelievable size of these monster ships.

The Danes didn’t appreciate Eric’s ambitious encroachment on their turf in the lucrative Baltic market and neither did the Hanseatic city of Lübeck. In 1563, the conflict escalated into the Northern Seven Years’ War. It was Sweden against Denmark–Norway, Lübeck and the Polish–Lithuanian union. Sweden’s navy was already intimidating compared to its rivals. It had 38 ships, 16 of them large warships. The Mars was armed with at least 100 guns, perhaps as many as 200, depending on which source you believe. Its heavy artillery enabled it to fight at a distance, eschewing the old-fashioned boarding followed by hand-to-hand combat tactics that had dominated naval warfare for so long. 

A dent from a cannon ball strike?

When the Mars and other Swedish warships went up against the fleets of Denmark, Lübeck and the Polish–Lithuanian union off the coast of the Swedish island of Öland on May 30th, 1564, at first Mars seemed to dominate the field. With those big guns of hers, she disabled the Danish flagship Fortuna and sank the Lübeckian ship Alte Bark. The Danish and Lübeckian commanders realized they would have to board her or face certain defeat. On day two of the engagement, they managed to do just that. The only problem is the Mars was on fire. The enemy crews only had enough time to board her and initiate looting procedures before they were all blown sky high in an explosion so powerful that it shot the ship’s mainmast straight up in the air like a crossbow bolt. The Mars sank quickly, taking many coins, cannons and lives to the cold Baltic seafloor with it.

And there it lay, in cold, silent repose, caressed by the quiet and gentle currents of the deep Baltic, until it was again discovered by the Swedes.

In 2011 the wreck of the Mars was found near Öland 250 feet below the surface of the water. Even though it went down in such a spectacular fashion, it was in excellent condition. Its guts were exposed in the explosion, but the wood has been perfectly preserved, and it's cannon were there as well, waiting patiently to be raised and used again in defense of the crown.

Via the always good History Blog.