Harald Bluetooth & Black Friday’s Bastard


The Bluetooth logo combines the runes for Harald’s initials.

On Black Friday, the day after US Thanksgiving, American retail shops unleash legions of deals upon consumers. As retailers attempt to milk more profits from consumers, a new tradition has arisen to induce people to shop online the Monday after Black Friday: Cyber Monday (or Cyber Week). This year, online retailers like Amazon, “celebrated” Cyber Week from December 1st to December 7th – and the sales totals are now in ($2.68 billion). So, in honor of Cyber Week – or simply as a way to bring you a tidbit of Viking history – here is the story of Bluetooth.


The face of the Viking king, Harald “Bluetooth” Gormson for whom the Bluetooth protocol was named. Source: Wikimedia Commons.

For those who quite understandably do not speak cybergeek, Bluetooth is a method (or communications protocol) that lets various electronic devices communicate with each other without using those annoying cables.

Devices like your mobile phone, laptop computer, iPad, and car use Bluetooth to connect to each other. Your smart phone uses Bluetooth to connect to wireless speakers and transmit music. Your wireless mouse or keyboard may connect to your laptop or desktop computer through Bluetooth. And, some cars let you hear phone calls over their stereo system with Bluetooth integration.


People can transfer information like photos and contacts between a laptop and a mobile phone by connecting these devices using Bluetooth. After the devices connect, the data is transferred through the air (using the Bluetooth protocol). People who use Bluetooth do not have to connect their devices with cables.

The name Bluetooth, and its distinctive logo, have their roots in Viking history. Way back in 1997, while Jim Kardach was co-developing the communications standard, he was reading Frans G. Bengtsson’s historical novel The Long Ships about the Vikings and King Harald Bluetooth.

King Harald (born c. 935 — died c. 986 CE) united the outlying tribes of Denmark. Harald was also known as “Bluetooth” or in Old Norse blátǫnn. There are several theories on how Harald acquired this nickname – the most common one being he had one blue or blackish rotten tooth. (The word for blue meant “dark.1 ”)


This headset uses Bluetooth to connect to a mobile phone.

Seventeen years ago, mobile phones and computers didn’t communicate with each other very well. The goal of Bluetooth was to unite mobile phones and PCs the way King Harald united, or conquered, the tribes of Denmark and Norway.

A key theme in King Harald’s rule was unification – and perhaps it had to be. Harald’s father, Gorm the Old, was the first in his dynasty. Gorm united northern Denmark under his rule and Harald continued his effort. Presumably, in addition to a quest for greater power, centralization made defense simpler. The Norse lands were constantly at war.

Harald focused on creating systems of protection, including roads, bridges, and fortresses. He improved existing fortresses and built new ones – notably many of the (at least) seven “Viking” (or Trelleborg) ring forts in Norway and southern Sweden.

Aggersborg Ring

Harald may have built these fortresses in response to his loss of Danevirke and parts of Southern Jutland to the Germans around 974.

While Harald was attempting to continue his father’s work of uniting Denmark under one rule, Denmark may have been in a mixed state of worshipping the Old (Norse) gods and the new (Christianity). This is controversial among historians, but some  have argued that German bishops may have been present in Denmark when Harald became king.

Originally a pagan, Harald may have converted to Christianity after the German king Otto the Great defeated him in battle. According to one source, Harald, along with his wife and son, were baptized when he swore fealty to Otto. If this is how it happened, we shouldn’t necessarily read too much into Harald’s piety.


The monk Poppo baptizes Harald Bluetooth. Source: Wikimedia Commons.


Conversion was a symbol of political submission and an obligation to pay a tithe, as one historian noted. And, as that historian notes, at least in this instance, it’s hard to tell conversion apart from conquest.2. Harald tried to get the Danish and Norwegians he ruled to become Christian – perhaps since Christianity could serve as a centralizing or unifying force.

Towards the end of Harald’s life, his hold on power began to disintegrate. For reasons that remain unclear, Harald lost control of the tribes he united in Denmark and even his own son turned against him. (Harald had to seek refuge in Wendland from him.) Some historians feel that Harald’s problems stem from his promotion of Christianity when many nobles still remained pagan.

The Bluetooth Logo


The Bluetooth logo.

The glowing blue Bluetooth logo combines the runes for Harald Bluetooth’s initials: H (haglaz haglaz-H-harald-bluetooth) and B (berkanan berkanan).

As a result of their close affinity with carving – the Norse were veritable magicians with wood — some historians believe that runes took on a spiky appearance to make it easier to carve them into wood and stone. (It is easier to move your knife to work a straight line over a curve.)

Wood was plentiful in the heavily forested Scandinavia and the region’s inhabitants developed superb carving skills. The genius underlying Viking longships and art work attest to this talent.


Viking longship design – note the how shallow the ship is. Wikimedia commons.

The longship’s long, narrow, and light design provided strength and agility. The ship’s shallow draft let it silently sail in water only three feet deep (1 m) and stealthily land on beaches. Yet the longship’s strength let it weather the rough North Atlantic where the ship’s agility let it pivot sharply to avoid icebergs. A crew of Vikings could carry these light ocean-faring ships across land to make a quick getaway.


Click image to enlarge. The intricately carved wood in the Oseberg ship depicts mythical animals like dragons intertwined with each other. Source: Wikimedia Commons.

Viking craftmanship and attention to detail also appears in their ornate yet detailed gold jewelry.


Click image to enlarge. Note the extremely detailed design of this gold Viking jewelry. From the Hiddensee Treasure from the National Museum of Denmark. Source: Wikimedia Commons.

It’s somehow comforting that a nearly forgotten Norse king – and an extinct alphabet – are now immortalized in technology. It is often overlooked, but the Norse were, in their own way, the Silicon Valley masterminds of their day.

© History Behind Game of Thrones. Unauthorized use or re-use is prohibited.

  1. Bluetooth also may have come from a corruption of the English word for chief (“thane”) and dark; Harald was a “dark chieftain.” Or, as one museum curator argues, Harald wore primarily blue clothing – akin to pricey purple clothing —  to emphasize his royalty. See http://en.wikipedia.org/wiki/Harald_Bluetooth  []
  2. See Timothy Reuter in Neil Lunds article “Harald Bluetooth – A Saint Very Nearly Made by Adam of Bremen” in The Scandinavians from the Vendel Period to the Tenth Century edited by Judith Jesch. []

Jamie Adair is the editor of History Behind Game of Thrones, a website about the history behind George RR Martin's "A Song of Ice and Fire" novels and the hit TV show, "Game of Thrones."


  • Reply December 20, 2014

    M.E. Lawrence

    My, my–that’s quite fascinating and will be sent on to some friends and particularly to my husband, who is fond of Viking sagas, art, etc.

    (By the way, in the East San Francisco Bay Area, specifically Berkeley and Oakland, we have a growing custom called Plaid Friday, in which consumers make a point of buying holiday gifts at locally owned indie shops; the idea is that our community is thus woven together in a way that buying corporate doesn’t encourage.)

  • Reply December 20, 2014

    Jamie Adair

    re: Bluetooth
    Glad you liked it. I work in high tech and when I first heard Bluetooth’s story, I was tickled pink. I wish more products would get such creative names.

    re: Plaid Friday
    Oh isn’t that nice! Plaid Friday puts Black Friday and Cyber Monday to shame. 🙂 That’s wonderful!

  • Reply December 21, 2014

    Watcher on the Couch

    Thank you for this informative article. The story of Harald Bluetooth is completely new to me and I had no idea that the name of the technology had a historical inspiration.

    I concur that Plaid Friday as explained by M.E. is a nice idea. There are sometimes Farmers’ Markets held on the Market Square in my home town (the traditional market has been held indoors for a great many years; I’m not saying it’s ALWAYS raining in England but when it does so it rains with a vengeance). Last time the majority of the produce in the Farmer’s Market was not particularly local – or particularly cheap. I cannot speak for the US but on the high street in many British towns there are as many charity (US thrift??) shops if not more than ordinary shops. Mind you, times have been tough since about 2007/08 so the charity shops are a lifeline for people who are not terribly well off.

    • Reply December 22, 2014

      M.E. Lawrence

      I am fortunate in living fairly near the Great Salad Bowl of California’s Central Valley, so our local farmers’ market is lush and delicious, even in December. Sadly, when I asked the manager at Basingstoke’s weekly market if he had any local something-or-other, he looked quite blank; I couldn’t decide if my question was silly or if he just wasn’t used to someone’s wanting to know.

      (On the other hand, British charity shops tend to be very fine, especially the RSPCA, Oxfam and British Heart Association; I always come home with cool gifts I bought for little money.)

      Anyway, Jamie, thanks again for the tale of Harald Bluetooth and the beautiful photos. And thanks to the Watcher on the Couch for one of the better cyber-names–it always makes me grin..

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