Eric I, Duke of Mecklenburg



Eric, Duke of Mecklenburg (after 1359, probably in 1365 –26 July 1397) was the eldest son of Albert, King of Sweden and heir to the throne of Sweden. Eric played a significant role in his father's attempts to secure and reclaim the Swedish throne. Eric and Albert were defeated in battle of Åsle in 1389 and imprisoned by the Danish Queen Margaret I of Denmark. They were released in 1395 against a ransom guaranteed by the Hanseatic league.

Albert tried to regain the Swedish crown by sending Eric to conquer Gotland in 1396. Eric briefly became the ruler of Gotland. Eric died in 1397, and his death led to the loss of Gotland from Mecklenburg to pirates, who were later conquered by the Teutonic Order.

Early life
Eric was the eldest son of Albert, King of Sweden (reigned 1364–1389) and Queen Richardis, a daughter of Count Otto I of Schwerin. The date and place of their marriage are not known. It is assumed that the wedding took place in Sweden after 1364, based on a contemporary genealogy that records Albert's betrothal and succession to the throne but omits mention of the marriage. Eric was likely born in Sweden and grew up there.

Imprisonment
Eric's father attempted to consolidate his position as King of Sweden in 1364 and again in 1386. The first mention of Eric in the chroniclers' records is from 1389, when Queen Margaret I of Denmark intervened and defeated Albert in the battle of Åsle, on the plains of Falköping in Västergötland. Albert and Eric were captured after the battle. The castles in Sweden surrendered to Margaret, who now became the ruler of the three Scandinavian kingdoms. In Sweden, only Stockholm remained in the hands of the Mecklenburgs, but even it was besieged by Margaret's troops.

To support Stockholm from the sea, the dukes of Mecklenburg employed a company of privateers, who later known as Vitalienbrüder, 'Victual brothers'. In 1391, the Mecklenburgs conquered Bornholm and Visby. The pirates obtained bases in Gotland and Finland and disrupted trade in the Baltic Sea. The Hansa started negotiations with Margaret in order restore their commercial rights in Baltic. In 1395, Albert and Eric were released against a large ransom after three years of negotiations involving Hinrich Westhof and Johann Niebur, the mayors of Lübeck. Stockholm was given as a pledge to the Hanseatic cities that guaranteed the ransom. If the ransom was not paid within three years, Stockholm would be given to Margaret.

After his release, Albert returned to Mecklenburg with his son and resumed his duties as the duke. On February 10-15 in 1396, a double wedding took place in Schwerin. Albert married the twice widowed Agnes of Brunswick-Lüneburg and Eric married Sophie, the daughter of Duke Bogislaw VI of Pomerania-Wolgast. Eric's and Sophie's marriage produced no children.

Master of Gotland
Albert could not raise the money for the ransom and attempted to reconquer his kingdom. In 1396, he tasked Eric with the reconquest of Gotland. In the summer or fall of 1396, Eric landed on the island with an army and began to build fortifications. Sven Sture had also arrived to the island with Danish troops. In the spring of 1397, with the help of Victual Brothers, Eric defeated Sven Sture, who was forced to change sides and swear allegiance to Albert III. After Sven Sture's defeat, Eric was the master of Gotland. Due to his association with the Victual Brothers and Sven Sture's men, he is sometimes portrayed as a pirate chieftain.

In June 1397 Eric, accompanied by Sven Sture's men, launched a failed surprize attack against Stockholm, now controlled by the Hanseatic league. Around the same time, the kingdoms of Denmark, Norway and Sweden were united into the Kalmar Union, which cemented the position of Queen Margaret and crushed Mecklenburg's hopes of regaining the Swedish crown.

Death and burial
Duke Eric died suddenly of some disease in 1397 at his fortress called Landeskrone or Klinteholm, located close to the port of Klintehamn, south of Visby in Gotland. After Eric's death, the dukes of Mecklenburg lost control of the island to the pirates, and had to withdraw from the island in April 1398 with Eric's widow Sophie and 400 men. The fortress of Landeskrona was destroyed in 1398 when the Teutonic Order and the leading Prussian cities conquered the island to put an end to piracy.

Eric was buried in St. Mary's Church, also known as Visby Cathedral, where part of his original tomb is on display. Notably, he was not buried in a prestigious place in the choir of the church. According to German historian Nikolaus Marschalk (d. 1525) this was because he died of plague. The reliability Marschalk's claim is questionable, as there is no known outbreak of plague from that time.