Medieval Scandinavia: The Rise and Fall of the Danish Kingdom

By Beñat Elortza Larrea

In the second article of this series about the rise of kingdoms in medieval Scandinavia, Beñat Elortza Larrea presents the history of Denmark between the late tenth and early fourteenth centuries.

The initial unification and consolidation of the Danish kingdom took place rather early, especially in comparison to the other Scandinavian countries. Frankish sources mention Danish kings by name as early as the ninth century, and archaeological evidence suggests that Denmark was a single entity by the 700s. From the mid-ninth century onwards, connections between the Danes and their Frankish and German neighbours to the south grew, as famed Christian missionaries such as Ansgar led proselytising efforts in the region. Rather little is known about Denmark, however, until the second half of the tenth century.


As elsewhere in Scandinavia, unification and Christianisation went hand-in-hand in Denmark. The Jelling runestone, raised near the royal complex of the same name, tells us that Harald Bluetooth ‘united all of Denmark under him and made the Danes Christian’. It is certain that Christianity had entered the Scandinavian stage before the 980s, but the runestone’s intent to correlate increased political control and the emergence of the new religion is nevertheless significant. Harald was not simply a convert himself, but he also persuaded – or forced – the Danish magnates to support the recognition of Christianity as the official religion. His power, moreover, was not limited to proselytising activities; Harald received tribute from the Norwegian kings and magnates, as well as wielding control in Denmark. During his reign, an impressive network of circular fortified camps – known as the Trelleborg fortresses – were built across Denmark.

Harald Bluetooth’s successes had primarily hinged upon his standing with the realm’s magnates and his martial prowess; his power, therefore, was reliant on continued successes, rather than on a well-established ideology of kingship. Sometime in the mid-980s, Harald’s son, Sweyn Forkbeard, rebelled against his father and drove him out of Denmark. The reigns of Sweyn and his son, Canute the Great, were even more expansionist and successful than Harald’s. Sweyn allied himself with Norwegian and Swedish aristocrats and, by 1000 CE, he had established himself as the undisputed king of Norway, which would be ruled by his allies, the jarls of Lade; Danish control over Norway – albeit with a few interregna – would last until Canute the Great’s death in 1035.


In 1013, the year before his death, Sweyn managed to bring England under his control after several unsuccessful attempts; Canute followed his father’s example, and conquered the English kingdom himself in 1016. Somewhat contradictorily, the conquest of England had consequential effects in the strengthening of the Danish kingdom. Anglo-Saxon legislation and ecclesiastical structures became well known to the Danish kings, who attempted to reproduce these innovations in Denmark. During this period, the Danish Church broke from its metropolitan diocese of Hamburg-Bremen, and appointed English bishops, thus taking the first steps towards an ecclesiastical administration outside German control.

Following Canute’s death in 1035, the North Sea Empire came crashing down. The Norwegian magnates elected a local king, Magnus the Good, and Canute’s son Harthacnut, attempting to hold onto both his English and Scandinavian domains, scarcely managed to do either. After his death in 1042, the Danes conclusively lost control over England, and Magnus of Norway reigned over Denmark until 1047. Following Magnus’s own death, Sweyn Estridsen became king in Denmark. He descended from Estrid, Sweyn Forkbeard’s daughter, and curiously chose to use a matronym – thus taking his mother’s name – as a way to project legitimacy. While Sweyn’s reign was fraught with conflict – most notably a protracted war against Norway and an unsuccessful expedition against Anglo-Norman England in 1070 – he managed to ensure Danish independence against Norwegian magnates and German bishops.

Between 1076 and 1134, five of Sweyn’s sons – none of them legitimate – would succeed each other: Harald III, Canute IV, Oluf I, Erik I and Niels. Very few offensive expeditions were launched during this period, but the Danish kings began to slowly cement their power. Canute IV, for instance, attempted to introduce a tax for neglecting military obligations to the Crown; this reform was poorly received, and the ensuing rebellion would lead to Canute’s murder in 1086. Successful reforms included the introduction of the formula dei gratia rex – king by the grace of God – which strengthened the kings’ status as divinely sanctioned rulers, and the establishment of a Scandinavian ecclesiastical province centred on Lund in 1104.

The delicate balance of fraternal succession, however, was not destined to last. By 1130, cracks had started to appear on its relatively stable surface, as Sweyn’s grandchildren began scheming against each other in order to ensure their eventual succession. Niels’s son was notoriously involved in the murder of one of his opponents, Canute Lavard, in 1130. Niels’s unjustified lenience towards this heinous act of kin slaying would trigger a rebellion against him; the incumbent king was soundly defeated at Fotevik in 1134, and was murdered by the townspeople of Schleswig. The rebellion against Niels set the now-inevitable events into motion.


Over the following twenty years, several scions of the Kyntling dynasty would vie for power in a series of wars. The later phase of these wars was characterised by the competition among three claimants: Sweyn III, Canute V and Valdemar I, the son of Canute Lavard, whose murder had precipitated these events. After having seemingly achieved a power-sharing compromise, Sweyn invited his co-kings to a banquet in Roskilde, where he attempted to murder them. While Canute was killed, Valdemar managed to escape to his powerbase of Jutland. Owing partially to his own tactical genius – but perhaps most importantly, to the strong alienation that Canute’s act had generated – Valdemar defeated Canute in a pitched engagement. The civil wars had ended.

Valdemar I of Denmark and Sweyn III of Denmark and Canute V of Denmark

The reigns of Valdemar I (r. 1157-1182) and his sons Canute VI (r. 1182-1202) and Valdemar II (r. 1202-1241) were extremely significant from a state-building perspective. Following the demise of almost every political opponent, Valdemar set out to solidify and centralise royal power. In 1170, Valdemar I was the first Danish king to be anointed and crowned, while his son Canute VI was crowned as junior king beside him. By appointing a junior ruler during his lifetime, Valdemar aimed to secure an orderly succession, as he also accentuated his dynasty’s rightful prominence.

Between 1157 and 1241, the Danish kings introduced substantial reforms. One of the most consequential reforms was the transformation of the naval levies – the lething – into a rotational coast guard under royal control, who provided the Crown with a seasonal fleet and permanent taxes; in addition, an aristocracy of service was established, whereby those individuals who served as heavy cavalry received exemptions from taxation. This period also oversaw the codification of the provincial laws. By writing down the laws, the Danish kings strengthened their judicial authority, as certain crimes carried automatic penalties such as exile or heavy fines that had to be paid directly to the Crown.


Valdemar and his sons also engaged in expansive campaigning in the Baltic. Valdemar I and Canute VI launched several expeditions against Pomerania, and forced the local aristocracy to submit to Danish authority. Valdemar II, on the other hand, conquered large swathes of Estonia and gained overlordship over a number of northern German towns; after a disastrous defeat in 1227, however, Denmark lost its German and Pomeranian vassals.

The successes of the Valdemarian kings contrast starkly with the period following Valdemar II’s death. The second half of the thirteenth century was characterised by open conflict between the late king’s children, most of whom vied for the throne. Valdemar’s eldest surviving son and successor, Erik IV, was murdered in 1250, possibly at the behest of his younger brother Abel, who would himself die in 1252. Yet another brother, Christoffer I, then usurped the throne, even though Abel had a legitimate son; this son, Valdemar, was awarded the duchy of Schleswig, thus creating a rivalling scion within the royal dynasty.

Eric V of Denmark

Conflict within the dynasty was further exacerbated by the archbishops’ demands for the recognition of wider ecclesiastical privileges, and relatively organised resistance from with the aristocracy, who opposed the Crown’s judicial and fiscal reforms. These tensions led to the establishment of the Danehof, a parliament comprising the realm’s lay and ecclesiastical magnates, which assembled once a year and advised – or pressured – the kings on legislative matters. In addition, Christoffer’s son and successor Erik V was forced to sign a håndfæstning – literally, hand-binding – in 1282; this document set out the limitations of royal rule, and described the Crown’s obligations towards the four estates of Denmark: the nobility, the Church, the peasantry and the burghers. The fragile balance achieved by these compromises was quickly upended on November 22, 1286, when Erik V was murdered by unknown assailants in Finderup. The murder would leave a faction of aristocrats, led by the queen dowager and Valdemar IV, duke of Schleswig, as regents.

After Erik V’s murder, his son Erik VI Menved would try to emulate Valdemar II’s successful conquests. Denmark became embroiled in several wars, most notably by intervening in the Swedish Brothers’ War and by launching expeditions against northern German towns such as Stralsund or Lübeck. Ongoing conflicts with the archbishop and the aristocracy meant that recruiting armies for these campaigns was difficult, and Erik resorted to hiring large mercenary forces. Abject defeats in all fronts made Erik hard-pressed for money to pay his stipendiaries, and he resorted to mortgaging parts of Denmark as payment.


When his brother Christoffer II acceded the throne in 1320, effective royal power was on its last legs; the Crown’s ability to establish new taxes was seriously hindered, and mortgage payments to the German debtors were piling up. When Christoffer II died in 1332, the Danish kingdom practically ceased to exist as the German mortgagees occupied the territories they had been promised. It would be eight years of occupation and revolts until Christoffer’s son, Valdemar, acceded the throne.

Beñat Elortza Larrea has a PhD from the University of Aberdeen, and he is currently finishing a Bernadotte postdoctoral fellowship at the University of Gothenburg. His research interests include state formation in medieval Scandinavia, military history from a social perspective, and maritime societies in the Middle Ages. Click here to visit his page on

Click here to read more from Beñat’s series on Medieval Scandinavia

Top Image: 17th century map of Denmark by Jan Janssonius