Kalmar Wars

At issue: Swedish independence

Date: 1409–1613

Location: Denmark and the Scandinavian peninsula

Combatants: Danes vs. Swedes

Principal commanders:Danish, Christian II (1481–1559); Swedish, Gustavus I Vasa (1496?-1560)

Principal battles: Brunkeberg, Lake äsunden, Axtorna, Bornholm

Result: Sweden achieves independence

Background

In 1388, Queen Margaret of Denmark succeeded to the throne of Norway, and in the same year, the Swedish nobility, after enduring decades of domestic instability and a series of weak rulers, elected Margaret as queen of Sweden. This personal union of the three kingdoms was transformed into a formal federation in 1397 by the Union of Kalmar. Although each kingdom retained a great deal of control over internal matters, Copenhagen would remain the center of power for the union, and Sweden became increasingly disaffected under Danish rule.

Action

The first major challenge to the Union of Kalmar came in the 1430’s. King Erik of Pomerania had engaged in a costly and ultimately unsuccessful war with the dukes of Holstein and the Hanseatic League (1422–1435). Erik’s attempts to raise taxes in order to finance his aggressive foreign policy led to a revolt in Sweden. The revolt, begun in 1434, spread quickly to Norway and eventually to Denmark. In 1439, the nobles of the three kingdoms deposed Erik and chose his nephew, Christopher of Bavaria, as ruler.

Christopher died in 1448, leaving no heirs, and the Danish nobility chose Christian of Oldenburg to succeed to the throne. In Sweden and Norway, however, Karl Knutsson was crowned king as Charles VIII, and a period followed in which both Christian and Karl contended for control and Sweden became embroiled in a confused civil war. After Karl’s death in 1470, Christian led a campaign to take Stockholm but was defeated by a Swedish army under Sten Sture at Brunkeberg (1471). As a result of this battle, Sten became the effective ruler of Sweden, although he did not formally end the Union of Kalmar.

Christian I’s successor, John, continued the struggle with Sten, and, in 1497, succeeded in driving him from Sweden. Sten returned in 1501, taking advantage of John’s preoccupation with a conflict on Denmark’s southern frontier, and another period of domestic turmoil ensued, continuing until 1512.

The tranquility that followed did not last long. John’s son, Christian II, attempted to reassert Danish predominance in Sweden, where Sten Sture the Younger, held sway as guardian of the realm. In 1520, Christian invaded Sweden and defeated Sten’s forces at the Battle of Lake äsunden. Christian then seized Stockholm and, in what became known as the Stockholm Bloodbath, he quickly ordered the executions of more than eighty rebel leaders.

The brutality of Christian’s measures sparked a widespread Swedish revolt, led by Gustavus Vasa. Meanwhile, Christian faced opposition in Denmark, where the nobility resisted the monarch’s attempts at centralization. In 1523, Christian fled to the Netherlands, and his uncle, Frederick I, was proclaimed king. In June of that year, Gustavus I was elected king of Sweden, which effectively ended the Union of Kalmar.

In the years immediately following the union’s demise, a shared fear of the exiled Christian II led to an alliance that temporarily suspended the struggle between the two rivals. In 1533, both states were drawn into a war against Lübeck, which merged with a Danish civil war known as the Count’s War (1533–1536). An allied naval force crushed the Lübecker fleet at the Battle of the Little Belt (1535). Lübeck agreed to peace the next year.

In 1563, the struggle between Sweden and Denmark resumed with the Seven Years’ War. Erik XIV had instituted reforms of the Swedish army and navy, but the war initially went badly for Sweden. The Danes captured the important fortress town of älvsborg at the outset of the war and later defeated the Swedish army at the Battle of Axtorna (1565). Swedish forces advanced into central Norway in 1564; although they were initially successful, it proved impossible to hold these conquests. A subsequent invasion of southern Norway led to the capture of Oslo (1567), but this too was retaken by the Danes.

Denmark’s navy held the Swedes in check until the Swedish fleet, led by Klas Kristersson Horn, defeated the Danes at Bornholm (1565). The Swedish Navy, from that point on, dominated the Baltic. Sweden, however, could not extract more advantages from this success because an internal revolt, sparked by Erik’s growing insanity, erupted in 1568. The next year, Erik was deposed and replaced by his brother, John III, who negotiated a peace with Denmark that restored the prewar status quo.

In the four decades following this conflict, Sweden became preoccupied with territorial expansion in the eastern Baltic and waged war against both Russia and Poland. In 1611, taking advantage of this situation, Christian IV declared war on Sweden. The Kalmar War of 1611–1613 took its name from the Swedish fortress that became the focus of Denmark’s war effort. The fortress held out against a vigorous Danish siege, and the young Gustavus II Adolphus led a series of diversionary actions that kept the Danes off balance. In 1612, Denmark took älvsborg, and a Danish force landed near Stockholm. These troops withdrew, however, when Gustavus Adolphus rushed troops to defend the capital. The two sides agreed to English mediation, and the Peace of Knäred (January, 1613) ended the war.

Aftermath

The Danish-Swedish wars ended the dream of a Scandinavian union forever. Although Denmark retained control over the sound and the lucrative tolls on Baltic trade, Sweden had achieved its independence and would soon gain the upper hand in its struggle with Denmark over supremacy in the Baltic.

Bibliography

Jesperson, Knud V. “Warfare and Society in the Baltic: 1500–1800.” In European Warfare: 1453–1815, edited by Jeremy Black. New York: St. Martin’s Press, 1999.

Oakley, Stewart. “War in the Baltic 1550–1790.” In The Origins of War in Early Modern Europe, edited by Jeremy Black. Edinburgh, Scotland: J. Donald, 1987.

Roberts, Michael. The Early Vasas: A History of Sweden, 1523–1611. Cambridge, England: Cambridge University Press, 1968.