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Two Kings · Act 1 · The king and the radio

How Bluetooth got its name: the history

The research behind 2:00–7:00 of the film · Watch this part

Bluetooth is named after Harald Bluetooth, who ruled Denmark from about 958 until about 986.3 In 1997 Intel's Jim Kardach proposed the king's name as a code name for a short-range radio whose idea started at Ericsson in Lund, Sweden.1285 The real name, PAN, failed the trademark search, so the placeholder shipped, and the logo is the king's initials written in runes.1011

Key facts

  • The idea started at Ericsson's mobile division in Lund, Sweden, in 1989; the design work began in 1994.56
  • In 1997, in Toronto, Intel's Jim Kardach and Ericsson's Sven Mattisson went out for beers, and Mattisson told Kardach about a tenth-century Danish king.12
  • Harald Bluetooth ruled Denmark from about 958 until about 986, and raised the great stone at Jelling around 965.34
  • Bluetooth was only a code name. The real name was going to be RadioWire or PAN; PAN failed the trademark search.810
  • The logo is the runes for H and B, Hagall and Bjarkan, written as one mark.11
  • Five companies formed the Bluetooth Special Interest Group in May 1998, and version 1.0 of the specification followed in July 1999.1213
  • The first Bluetooth product was a headset, which Ericsson unveiled in Las Vegas in November 1999.14

20

facts cited

21

sources, 14 primary

4

common claims corrected

7

archival images

What this part says

The narration, line by line, as it is spoken in the film.

Toronto, 1997

In 1997, at a meeting in Toronto, two engineers went out for beers: Jim Kardach from Intel, and Sven Mattisson from Ericsson.1

Mattisson had been reading The Long Ships, a Swedish novel about Vikings, and he told Kardach about a king.2

I want to start with that king, because his name is on the device in your pocket, and on the board on my bench.

The king was Danish, and he had been dead for about a thousand years.23

So before the radio, a short trip: across the Atlantic, to Denmark.13

The king

Harald Bluetooth ruled Denmark from about 958 until about 986.3

Around 965 he raised a great stone at Jelling for his parents. It says he won for himself all of Denmark and Norway, and made the Danes Christian.4

A king who brought together people who didn't speak to each other. Hold on to that. It's the whole film.

Denmark and Norway: two peoples, one king, and a stone to say so.4

Lund, before the name

The radio Mattisson worked on was older than that night in Toronto. The idea started at Ericsson's mobile division in Lund, Sweden, in 1989, with its technical chief, Nils Rydbeck, and Johan Ullman.5

The real design work began in 1994, when two engineers, Jaap Haartsen and Sven Mattisson, were asked for a short-range radio to replace the cable between a phone and a headset.6

One cable. That was the whole brief.

Replacing a cable sounds simple. But a cable never has to share the air.

Never sit still

Their answer was a radio that never sits still.

Classic Bluetooth splits the 2.4-gigahertz band into 79 channels, and hops between them up to 1,600 times a second.7

A noisy channel only costs it a moment. By then it's somewhere else.7

The placeholder

Kardach went home and read a history, Gwyn Jones's The Vikings, and found the king's runestone in it.2

He proposed the king's name as a code name, a placeholder.8

Then he made a slide: a figure carved on Harald's runestone, a phone in one hand and a laptop in the other. The pitch was that one radio could unite the computer and the phone.9

Later he found out the figure wasn't the king at all. It was Christ.9

The real name was going to be something sensible: RadioWire, or PAN. PAN won the vote, then failed the trademark search. So the placeholder shipped.10

A code name, borrowed from a Danish king, and it stuck.8103

The pitch outlived the slide: a phone in one hand, a laptop in the other, carved in stone.9

His initials

Even the logo is his. It's his initials: the runes for H and B, Hagall and Bjarkan, written as one mark.11

Five rivals, one radio

In May 1998, five companies (Ericsson, IBM, Intel, Nokia and Toshiba) formed the Bluetooth Special Interest Group.12

The first specification, version 1.0, followed in July 1999.13

Competitors, agreeing on one radio. A small unification of its own.

The first thing it did

And the first Bluetooth product was, fittingly, a headset. Ericsson unveiled it in Las Vegas in November 1999, and it shipped the following year.14

The first Bluetooth phone Ericsson showed never reached the shops. The T39 did, in 2001.15

The cable between the phone and the headset was gone. Exactly the brief.

The other king

So the radio had its king.

The other king in this story ruled Italy a thousand years ago, from 1002 to 1014. Before his name reached a circuit board, it went over a bar in a town called Ivrea.1617

From Harald's stone in Jelling, to Arduin's town, Ivrea.418

Stories that are usually told wrong

Common questions

How did Bluetooth get its name?

It is named after a tenth-century Danish king, Harald Bluetooth. In 1997, at a meeting in Toronto, Intel's Jim Kardach and Ericsson's Sven Mattisson went out for beers. Mattisson had been reading The Long Ships, a Swedish novel about Vikings, and told Kardach about a tenth-century Danish king. Kardach then read Gwyn Jones's history, The Vikings, and found the king's runestone in it. He proposed the king's name as a code name, a placeholder. The real name was going to be RadioWire or PAN. PAN won the vote, then failed the trademark search, so the placeholder shipped.12810

Who was Harald Bluetooth?

Harald Bluetooth ruled Denmark from about 958 until about 986. Around 965 he raised a great stone at Jelling for his parents. It says he 'won for himself all of Denmark and Norway and made the Danes Christian.'34

What does the Bluetooth logo mean?

The logo is his initials: the runes for H and B, Hagall and Bjarkan, written as one mark.11

Who invented Bluetooth?

The idea started at Ericsson's mobile division in Lund, Sweden, in 1989, with its technical chief, Nils Rydbeck, and Johan Ullman. The design work began in 1994, when two engineers, Jaap Haartsen and Sven Mattisson, were asked for a short-range radio to replace the cable between a phone and a headset.56

What was Bluetooth almost called?

The real name was going to be RadioWire or PAN. PAN won the vote, then failed the trademark search, so the placeholder shipped.10

What was the first Bluetooth product?

The first specification, version 1.0, followed in July 1999. The first Bluetooth product was, fittingly, a headset. Ericsson unveiled it in Las Vegas in November 1999, and it shipped the following year.1314

The facts and their sources

Primary sources come first: the organisation, person or document itself. Secondary sources are reputable press or reference works.

  1. 1

    In 1997, at a meeting in Toronto, Intel's Jim Kardach and Ericsson's Sven Mattisson went out for beers.

  2. 2

    Mattisson had been reading The Long Ships, a Swedish novel about Vikings, and told Kardach about a tenth-century Danish king. Kardach then read Gwyn Jones's history, The Vikings, and found the king's runestone in it.

    Often told as: Kardach read The Long Ships.
    Why that is not right: The novel was Mattisson's, not Kardach's.
  3. 3

    Harald Bluetooth ruled Denmark from about 958 until about 986.

  4. 4

    Around 965 he raised a great stone at Jelling for his parents. It says he 'won for himself all of Denmark and Norway and made the Danes Christian.'

  5. 5

    The idea started at Ericsson's mobile division in Lund, Sweden, in 1989, with its technical chief, Nils Rydbeck, and Johan Ullman.

    Often told as: Bluetooth began at Ericsson Mobile in Lund in 1994.
    Why that is not right: 1989 is the start of the idea; 1994 is when the design work began.
  6. 6

    The design work began in 1994, when two engineers, Jaap Haartsen and Sven Mattisson, were asked for a short-range radio to replace the cable between a phone and a headset.

  7. 7

    Classic Bluetooth splits the 2.4-gigahertz band into 79 channels and hops between them up to 1,600 times a second.

  8. 8

    He proposed the king's name as a code name, a placeholder.

  9. 9

    Kardach made a slide: a figure carved on Harald's runestone, holding a phone in one hand and a laptop in the other. The pitch was that one radio could unite the computer and the phone. Later he found out the figure wasn't the king at all. It was Christ.

    Often told as: Kardach's slide showed King Harald on his runestone holding a phone and a laptop.
    Why that is not right: Kardach's own account says the figure (side C of the large Jelling stone, marks on the palms) is Christ, and he quietly stopped using the image.
  10. 10

    The real name was going to be RadioWire or PAN. PAN won the vote, then failed the trademark search, so the placeholder shipped.

  11. 11

    The logo is his initials: the runes for H and B, Hagall and Bjarkan, written as one mark.

  12. 12

    In May 1998, five companies (Ericsson, IBM, Intel, Nokia and Toshiba) formed the Bluetooth Special Interest Group.

  13. 13

    The first specification, version 1.0, followed in July 1999.

  14. 14

    The first Bluetooth product was, fittingly, a headset. Ericsson unveiled it in Las Vegas in November 1999, and it shipped the following year.

  15. 15

    The first Bluetooth phone Ericsson showed never reached the shops. The T39 did, in 2001.

  16. 16

    The bar was named after Arduin, a local lord who was King of Italy from 1002 to 1014.

  17. 17

    They named it after the bar where they drank, the Bar di Re Arduino.

  18. 18

    Around 990 a lord named Arduin took over the march of Ivrea. He fought the Church for land, and in 997 his men killed the bishop of Vercelli. Two years later, in Rome, in front of the emperor and the pope, Arduin admitted he had led them.

  19. 19

    In 2011, digging beside the stone, archaeologists found its original footing. After more than a thousand years, it still stands exactly where Harald put it. Today it stands behind glass.

  20. 20

    It was almost certainly painted once. No colour survives on it now, so the painted copies you see are the museum's best reconstruction of how it looked.

    Often told as: The Jelling stone was originally painted, and paint traces survive on it; museum reconstructions follow those traces.
    Why that is not right: The National Museum says both 'the large rune stone was surely painted in strong colours' (Hvass 2011) and 'we don't know if Harald's rune stone was originally painted' (teaching page). Its 2020 news: 'time has gnawed all the colour off ... today only the pattern remains on the original.' Reconstructions draw on other finds: painted wood from the North Mound burial chamber, red-orange paint on the Bjerring rune stone, the Hørning plank. The 'fragments of paint in the engravings' claim (blogs) has no museum source.

The images

Real photographs and documents used in this part, with their credits and licences. Tap one to see the original.

Jelling: Harald's large runestone (whole stone)
Jelling: Harald's large runestone (whole stone)Ljunie / Wikimedia Commons / CC BY-SA 4.0
Jelling: Harald's large runestone (whole stone)
Jelling: Harald's large runestone (whole stone)Ljunie / Wikimedia Commons / CC BY-SA 4.0
Large Jelling stone, National Museum of Denmark photo
Large Jelling stone, National Museum of Denmark photoPhoto: Roberto Fortuna, National Museum of Denmark / Wikimedia Commons / CC BY-SA 3.0
Ericsson's buildings at Ideon / Brunnshög, Lund (2021)
Ericsson's buildings at Ideon / Brunnshög, Lund (2021)Johan Wessman / News Øresund / Wikimedia Commons / CC BY 2.0
Christ face of the Jelling stone (side C), painted replica
Christ face of the Jelling stone (side C), painted replicaMatt Brown / Wikimedia Commons / CC BY 2.0
The Bluetooth runestone Ericsson raised in Lund (1999): a man holding a laptop and a phone
The Bluetooth runestone Ericsson raised in Lund (1999): a man holding a laptop and a phoneKarl Baron / Wikimedia Commons / CC BY 2.0
Ericsson T39m (2001), unused in its original box, Tekniska museet
Ericsson T39m (2001), unused in its original box, Tekniska museetPhoto: Peter Häll, Tekniska museet / CC BY 4.0

Dramatised scenes

Places, people and eras for which no footage exists, reconstructed for the film. They are marked DRAMATISATION on screen.

Snow falls past the tall window of a small bar at night; warm light inside.
DramatisationSnow falls past the tall window of a small bar at night; warm light inside.
Two pint glasses on a scarred table; two hands at rest; snow beyond the window.
DramatisationTwo pint glasses on a scarred table; two hands at rest; snow beyond the window.
A worn paperback face-down by a pint glass on the bar table.
DramatisationA worn paperback face-down by a pint glass on the bar table.
A long timber hall by firelight: the hearth burns low, smoke climbs to the rafters.
DramatisationA long timber hall by firelight: the hearth burns low, smoke climbs to the rafters.
The king on his high seat, seen from behind; the fire beyond him.
DramatisationThe king on his high seat, seen from behind; the fire beyond him.
A file of riders crosses an open heath under a low grey sky, seen from far off.
DramatisationA file of riders crosses an open heath under a low grey sky, seen from far off.
Hooves and legs of a horse moving through heather, close and low.
DramatisationHooves and legs of a horse moving through heather, close and low.
The great stone half-raised on timber props, ropes taut to a team pulling from behind.
DramatisationThe great stone half-raised on timber props, ropes taut to a team pulling from behind.
An early-1990s engineering office on a winter afternoon: rows of desks, boxy monitors, snow outside.
DramatisationAn early-1990s engineering office on a winter afternoon: rows of desks, boxy monitors, snow outside.
A phone and a corded headset on a desk; a hand lifts the headset and the coiled cable pulls taut.
DramatisationA phone and a corded headset on a desk; a hand lifts the headset and the coiled cable pulls taut.
A tall office window in Lund on a winter afternoon, snow falling past half-open blinds.
DramatisationA tall office window in Lund on a winter afternoon, snow falling past half-open blinds.
An open history book under a reading lamp at night.
DramatisationAn open history book under a reading lamp at night.
A long meeting table in 1998, five chairs pushed in, pale morning light.
DramatisationA long meeting table in 1998, five chairs pushed in, pale morning light.
A 1999 trade-show floor seen from behind the crowd: aisles of glowing booths under black trusses.
DramatisationA 1999 trade-show floor seen from behind the crowd: aisles of glowing booths under black trusses.
A small glass case on a white plinth under one spotlight; inside, a silver earpiece, soft.
DramatisationA small glass case on a white plinth under one spotlight; inside, a silver earpiece, soft.
A city's night lights through a coach window, all soft discs of colour.
DramatisationA city's night lights through a coach window, all soft discs of colour.
The standing stone between the mounds at dusk, a silhouette against the last gold.
DramatisationThe standing stone between the mounds at dusk, a silhouette against the last gold.
The Ivrea street at night, the lit bar window framed by a stone doorway.
DramatisationThe Ivrea street at night, the lit bar window framed by a stone doorway.
The wrought-iron bracket above the bar window, the sign edge-on in the glare, swaying.
DramatisationThe wrought-iron bracket above the bar window, the sign edge-on in the glare, swaying.
40:00
WATCH ON YOUTUBE

Two Kings: a history of Arduino and Bluetooth

This part starts at 2:00. The full film is 40:00 long: two kings, a radio, a board, and how they ended up on the same bench.

Link added at release

All sources

Two Kings: a history of Arduino and Bluetooth, by Troniction. The Bluetooth® word mark and logos are registered trademarks owned by Bluetooth SIG, Inc. Arduino® is a trademark of Arduino S.r.l. Neither endorses this film. Image credits and licences are listed with each image.