The wreck of the 16th century Swedish warship Mars was discovered last year after two decades of searching, but divers were only able to make a cursory initial exploration of the site at that time. This year, a team of divers, researchers and a documentary film crew returned to the Mars to explore it in depth during the first two weeks of July. They found three silver coins from 1563, the year before the Mars sank in a naval battle off the northern tip of the island of Oland in the Baltic Sea. The coins are Swedish silver dalers bearing the image of King Eric XIV (reigned 1560-1568) in the royal regalia and his motto “Deus dat cui vult,” meaning God gives to whom He wishes.
The discovery of these particular coins is more evidence that the wreck is of the Mars, not just because the dating is so on point. The daler wasn’t an internal Swedish trade currency. That was the mark, which went into a devaluation spiral during the Nordic Seven Years’ War (1563–70), the war between Sweden-Finland and Denmark-Lübeck that the Mars was fighting in when it went down. The silver daler was an international coin minted in Sweden-Finland from 1534 until 1873. Much like the earlier and more widespread Spanish pieces of eight, the daler retained its silver weight and purity and was thus accepted elsewhere in the world. As the story has it, Admiral Jakob Bagge had 200,000 silver dalers with him on the Mars to use hiring mercenaries.
The diving team expects there are many more dalers on the wreck, but the cold, darkness and depth of the site make exploring it extremely time consuming. Professional divers have to carry a special mixture of gasses in their oxygen tanks to avoid the bends, and it still takes them about two hours to rise the 230 feet from the wreck on the sea floor to the surface. They can’t stay down there for long, even in the peak of the summer, before it gets too cold to stand.
Despite these strictures, researchers have been able to document the general map of the wreck site. Because of the dramatic way the Mars went down — according to contemporary eye-witness reports, the ship exploded, sending the main mast shooting straight up into the sky like an arrow — there are artifacts scattered as far as 500 feet from the central wreck. East of the wreck divers have spotted debris that could be the famous mast, but they haven’t investigated it yet.
Despite the explosion, the Mars is still intact in large parts. The massive wood boards still have visible cut marks left by the axes of the carpenters, and traces of white paint are visible in some places. The port hull is almost entirely intact; heavy cannons still stick out of rows of cannon ports. The starboard side has collapsed outwards, exposing the guts of the ship. Divers have swum into the stern and examined an area they think was the admiral’s quarters.
Some human skeletal remains have also been found. The Mars carried a crew of about 670 people, 350 sailors and the rest soldiers. Most of these were enlisted men rather than mercenaries.
There are cannons all over the sea floor. Documentary sources differ on how many cannons the Mars was equipped with, but the smallest number is 107, most of them muzzle-loading bronze cannons. The largest estimate puts the number at 173. Swedish naval artillery was key to their military strength. They had fewer troops, but their cast bronze cannons shot harder and farther than the Danish chamber-loaded iron cannons. The Danish fleet aimed to board, while the numerically inferior Swedes sought to avoid hand-to-hand combat and focus on distance artillery shelling.
Under Admiral Bagge, these tactics were highly effective. In fact, they were effective on May 30th, 1564, when the battle of Oland began. The Swedish ships showered the Danish-Lübeckian navy with cannon fire. The Danish flagship Fortuna alone was hit by 167 projectiles. After the first day, the Danes decided that the next day, they had to board the Mars at all costs or the battle would be lost.
Come the dawn of May 31st, most of the Swedish ships had dispersed, leaving the Mars with little support. Bagge went on the attack anyway — he was already a legend in his own time for his skill and courage — chasing the Danish fleet north with only the Mars, the Elephant and the Swan. It almost worked, but then the wind turned, giving some of the Lübeckian ships a chance to get close to the Mars.
Initial boarding attempts were repulsed by the Mars’ artillery, but then the ship caught fire, either due to a cannon exploding or from bombs and grenades lobbed by the Lübeckians. In hand-to-hand combat, Bagge’s troops were defeated by the superior numbers of the enemy and the fire on his ship. He and a hundred crew members surrendered and were transferred to a Lübeckian ship. Several hundred Lübeckians swarmed the Mars to plunder it. The fire was still raging, however, and while the boarders were looting, the powder kegs exploded. As many as 1000 men were left on board when the explosion took the Mars to the bottom of the sea.
Admiral Bagge was kept prisoner in Copenhagen from 1564 to 1571. A year after the war was over, he was finally released and returned to Stockholm where he was given a title, an estate and a cushy job at the Royal Palace, a position he held until his death in 1577.
The Deep Sea Productions film crew is capturing 3D and high definition film of the site which will be released as a documentary in the near future. Meanwhile, here is a Swedish news story that includes some beautiful footage of the Mars wreck.
For a beautiful photo gallery, sonar map and infographic of the wreck, see this article in the Svenska Dagbladet newspaper.