Bluetooth technology owes its name to the 10th-century Scandinavian king Harald “Bluetooth” Gormsson, the son of King Gorm the Old and of Thyra Dannebod, who ruled as king of Denmark from c. 958 to c. 986. He introduced Christianity to Denmark and consolidated his rule over most of Jutland and Zealand, whereas his rule as king of Norway most likely did not last for more than a few years in the 970s. The Bluetooth wireless technology was named after him: as the concept goes, it would unite devices the way Harald Bluetooth united the tribes of Denmark into a single kingdom. The Bluetooth logo consists of a combination of the H (ᚼ) and B (ᛒ) runes (for his initials) into a single graphic design.