Harald I of Denmark (The Kalmar Union)

Harald I Bluetooth, Harald Blåtand Gormsen, (also Harald III of Viken) was the first Christian king of Denmark. His reign saw considerable conflict both within Scandinavia and outside of it, especially with the Holy Roman Empire.

Denmark was largely quiet during Harald's reign. He built large forts in Scania and Jutland to cement and consolidate his reign and was effectively free to pursue foreign adventures. In this he was not always successful and the sagas are not always kind to him. He assisted the ruler of Normandy, Richard the Fearless, and sponsored raids into Prussia. He had dealings with the Swedes but was usually bettered by them and would have to supply them with first his daughter, then a fleet to keep them at bay. Successive alliances with the pagan Obodrites had mixed results in pushing the German Emperors southwards out of Jutland but possibily his long-term achievement was to bring Viken into the Danish sphere.

Harald II Greycloak had wrested the throne of Viken from Tryggve Olafsson in 963 with the implicit support of Harald Bluetooth (he was Harald Greycloak's uncle). However Harald Greycloak's reign soon ran into trouble and he was killed in Denmark in 970. Harald then settled the tricky subject of succession over the Norwegian kingdoms. Taking Viken for himself he gave Hordaland to the Earl of Lade, Haakon Sigurdsson. In the process he was recognised as High King of Norway, though this would realistically only a be a nominal title. Although Harald's rule over Viken could hardly be described as total, and it would frequently be divided from Denmark, this marked the first stage in Viken's long journey towards becoming one of Denmark's core provinces.

Although it is uncertain it was probably due to either Emperor Otto I or II's victory over Harald in the 960s that he came to be baptised. Harald appeared to embrace his new religion wholeheartedly. Even so there was limited growth in Christianity in Denmark and Viken during his lifetime.

He was killed in c. 985 during a revolt by his son Sweyn Forkbeard.