One main political motives for its formation was to block German expansion northward into the Baltic region. The main reason for its eventual failure to survive was the perpetual struggle between the monarch, who wanted a strong unified state, and the Swedish and Danish nobility, which did not. Diverging interests (especially the Swedish nobility’s dissatisfaction with the dominant role played by Denmark and Holstein) gave rise to a conflict that would hamper the union in several intervals from the 1430s until its definitive breakup in 1523, when Gustav Vasa was elected as king of Sweden.

After 1523 the Kingdom of Norway continued to remain a part of the Kingdom of Denmark under the Oldenburg dynasty for nearly three centuries, until its dissolution in 1814. Norway was then United with Sweden with this union lasting until 1905, when a grandson of the incumbent King Christian IX of Denmark, Prince Carl of Denmark, was elected as King Haakon VII of Norway; his direct descendants still reign in Norway.

Inception

The union was the work of Scandinavian aristocracy wishing to counter the influence of the German Hanseatic League. The force behind the Kalmar Union was Margrethe I of Denmark (1353–1412).

Margrethe I of Denmark, Norway and Sweden.

Margrethe I of Denmark was a daughter of King Waldemar IV of Denmar and Helvig of Schleswig. (Helvig of Schleswig was the daughter of Eric II, Duke of Schleswig, and Adelaide of Holstein-Rendsburg, and the sister of Waldemar V, Duke of Schleswig. Her date of birth is not known, but she and her brother were children at the time of her father’s death in 1325, and she is estimated to have been born in around the year 1320).

Margrethe I of Denmark married King Haakon VI of Norway and Sweden, who was the son of King Magnus IV of Sweden, Norway and Scania. In 1375 Margrethe succeeded in having her son Olaf recognized as heir to the throne of Denmark despite the claims of her elder sister’s Ingeborg’s husband, Duke Heinrich III of Mecklenburg, and their son Albert. Margrethe insisted that Olaf be proclaimed rightful heir of Sweden, among his other titles. In 1376 Olaf inherited the crown of Denmark as King Olaf II, upon the death of his maternal grandfather, King Waldemar IV of Denmark, with his mother as guardian. When his father, King Haakon VI of Norway died in 1380, Olaf also inherited the crown of Norway as King Olaf IV.

Margrethe became regent of Denmark and Norway when her only child, King Olaf II-IV of Denmark and Norway, died in 1387, leaving her without an heir. That same year she adopted her great-nephew, Bogislav, and his sister Catherine of Pomerania (grandchildren of Duke Heinrich III of Mecklenburg). Bogislav changed his name to Erik

Meanwhile in Sweden…

In 1363, members of the Swedish Council of Aristocracy, led by Bo Jonsson Grip, had been banished from Sweden after a revolt against King Magnus IV who was unpopular with the nobility. Members of the Swedish Council of Aristocracy arrived at the court of Mecklenburg where the nobles requested that Albert of Mecklenburg launch an invasion of Sweden. Albert was supported by several German dukes and counts and several Hanseatic cities in Northern Germany. Stockholm and Kalmar in Sweden, with large Hanseatic populations, also welcomed the intervention.

Albert was proclaimed King of Sweden and officially crowned on February 18, 1364. The coronation took place at the Stones of Mora. A fragment still remains of the stone commemorating the occasion called the Three Crowns stone. This is the earliest known example of the use of the three crowns as a national symbol for Sweden.

Background on Albert of Mecklenburg

Albert was the second son of Duke Albert II of Mecklenburg and Euphemia Eriksdotter, the daughter of Duke Erik Magnusson of Södermanland and sister of King Magnus IV-VII of Swede-Norway. Albert married Richardis of Schwerin, daughter of count Otto of Schwerin. Queen Richardis died in 1377 and was buried in Stockholm.

In 1384 he inherited the ducal title of Duke of Mecklenburg-Schwerin as Albert III and united it with Sweden in a personal union. Albert based his claims on the Swedish crown upon two family ties: his mother was the sister King Magnus IV-VII of Sweden-Norway whose paternal grandfather was King Magnus III of Sweden. Albert claimed first place in the Swedish order of succcession after the dethronement or deaths of all of the children of Magnus IV; and through a Swedish princess Christina, a daughter of King Sverker II who was King of Sweden from 1196 to 1208.

Albert of Sweden deposed

Albert kept the crown of Sweden for another 19 years, but most of western Sweden did not support his reign. When he attempted to introduce reduction of the large estates of the Swedish nobility, he lost his support in Stockholm. In 1389, facing a loss of landholdings and wealth, the Swedish nobility turned to Margrethe of Denmark widow to plead for help in getting rid of Albert. Queen Margrethe sent troops to Sweden and in February 1389, they defeated Albert at the Battle of Åsle.

Albert was captured, deposed and sent to Lindholmen Castle in Scania, where he spent the next six years imprisoned. He was released after 16 days of peace negotiations in 1395, during which he agreed to either give up Stockholm within three years, or pay large sums in retribution to Margrethe. When the three years were up, Albert’s (then) only son Eric had died after ruling Gotland in Sweden for a short time as instigated by his father, and Albert chose to give up Stockholm rather than pay the fine. In 1398 the agreement came into force, granting Margrethe possession of Stockholm.

At a conference held at Dalaborg Castle in March 1388, after Margrethe’s defeat of Albert, the Swedes were compelled to accept all of Margrethe’s conditions, elected her “Sovereign Lady and Ruler”, and committed themselves to accept any king she chose to appoint. Albert, who had called her “King Pantsless” returned from Mecklenburg with an army of mercenaries. On February 24, 1389, the decisive battle took place at either Aasle or Falan near Falköping. General Henrik Parow, the Mecklenburger commander of Margrethe’s forces, was killed in battle, but he managed to win it for her. Margrethe was now the omnipotent mistress of three kingdoms.

The defeated Albert married as his second wife Agnes of Brunswick-Lüneburg the daughter of Duke Magnus II of Brunswick-Lüneburg (d. 1373) and Catharine of Anhalt-Bernburg (d. 1390). Albert continued to reigned as Duke Albert III of Mecklenburg-Schwerin until his death, seven months before Margrethe’s in 1412. He finally and formally abdicated his Swedish throne in 1405, but until then still styled himself King of Sweden and his second wife Queen Agnes. His tomb is in the Doberan Minster in Bad Doberan, Germany.

Kalmar Union: 1397-1523.

In 1389 Margrethe proclaimed her great-nephew Erik of Pomerania as King Erik III of Norway (1389–1442). In 1396 he was proclaimed as King Erik VII of Denmark King and Erik XIII of Sweden (1396–1434, 1436–39) On June 17, 1397, Erik was crowned a king of the three Nordic countries in the cathedral of Kalmar. At the same time, a union treaty was drafted, declaring the establishment of what has become known as the Kalmar Union (Kalmarunionen). Queen Margrethe however, remained the de facto ruler of the three kingdoms until her death in 1412. Erik was ultimately deposed from all three kingdoms of the union, but in 1449 he inherited one of the partitions of the Duchy of Pomerania and ruled it as duke until his death.

Ambiguities concerning titles of Margrethe of Denmark, Norway and Sweden.

In Denmark Margaret was called “sovereign lady and lord and guardian of the entire kingdom of Denmark” (Norway and Sweden later bestowed on her similar titles). This special, double-gendered title bestowed upon the holder the power and authority of a man (lord), of a woman (sovereign lady) and of the gender-neutral guardian. Later, when Erik was elected King of Norway in 1392, she renounced this title in Norway, and in 1396, when he was crowned as King of Denmark and Sweden, she stopped the use of this title altogether, although she continued as Regent.

She only styled herself Queen of Denmark in 1375, usually referring to herself as “Margrethe, by the grace of God, daughter of Waldemar IV, King of Denmark” and “Denmark’s rightful heir” when referring to her position in Denmark. Her title in Denmark was derived from her father King Waldemar IV of Denmark. Others simply referred to her as the “Lady Queen”, without specifying what she was queen of, but not so Pope Boniface IX, who in his letters styled her “our beloved daughter in Christ, Margrethe, most excellent Queen of Denmark, Sweden and Norway”.

When she married Haakon VI of Norway in 1363, he was co-King of Sweden, making Margrethe Queen Consort, and despite being deposed, they never relinquished the title. In theory, when the Swedes deposed Albert of Mecklenburg in 1389 simply restored Margrethe to her original position as Queen Consort. Margrethe held these titles from March 1363 to 28 October 1412, she was Queen of Denmark, Norway and Sweden and founder of the Kalmar Union, which united the Scandinavian countries for over a century. She acted as Queen Regnant of Denmark, although in those days it was not the Danish custom for a woman to reign.