STOCKHOLM, SWEDEN—According to a Miami Herald report, weapons that may have been used to repel pirates have been found in a medieval shipwreck in the Baltic Sea, off the coast of Maderö Island. Although the wreckage was explored in 1969, a systematic study of it was not conducted until 2022. “Not so much is known about the architecture of these ships so every new wreck that is surveyed increases our knowledge a lot,” said research team member Niklas Eriksson of Stockholm University. Dendrochronological analysis of wood samples from the vessel indicates that at least some of the wood came from a tree felled in 1467. The variety of wood in the construction suggests that the Maderö ship was built at a shipyard that brought in and imported material from a larger area, rather than relying on locally grown wood, he added. Chemical analysis of samples of the cargo, including rectangular bricks, specialty bricks for lining windows and doors, and roof tiles, shows that they were made in northeastern Germany. The ship may therefore have been linked to the organized northern German merchant communities known as the Hanseatic League. A coating of sulfur on a cannonball at the site suggests that it may have been loaded in a cannon with gunpowder when the vessel sank. “During the fourteenth to fifteenth century, there [was] a lot of piracy on the Baltic Sea,” Eriksson explained. Read the original scholarly article about this research in International Journal of Nautical Archaeology. To read about investigations of the wreckage of a sixteenth-century Swedish warship, go to "Mars Explored."