"Bluetooth" was the code-name given by engineers from Ericsson to honor a tenth-century Viking king, Harald Bluetooth, who reigned from 940 to 985. He was credited for unifying Denmark, bringing order to the country. In all honesty, Harald's name was actually Blåtand, but was roughly translated in English as "Bluetooth." But don't take this to mean the color of his teeth were blue. Blåtand actually referred to the color of Harald's hair, which was a very dark color that was not typical of Vikings.
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