Why was a 9th century Viking woman buried with a ring that says ‘for Allah’ on it?

In the modernera, Scandinavian countries have
become known for their sometimes awkward
embrace of migrants from the Arab and Muslim
world. But the history behind that relationship
goes back far further than you might expect.
Consider the case of a ring discovered in a Viking
grave in Birka, a historic trading center in what is
now Sweden. The woman in the grave died in the
9th century and was discovered around a
thousand years later by the famous Swedish
archaeologist Hjalmar Stolpe, who spent years
excavating the grave sites around Birka.
The ring is unique. Made of silver alloy, it
contained a stone with an inscription written in
the Kufic Arabic script widely used between the
8th and 10th centuries. "For/to Allah," the
inscription read. It was the only known Viking
Age ring with an Arabic inscription to be found in
the entire of Scandinavia. Exactly how the woman
got the ring wasn't clear – she was found
wearing typical Scandinavian dress, so
presumably the ring arrived through trade.
Now, new research from biophysicist Sebastian
Wärmländer of Stockholm University and his
colleagues has confirmed exactly how unique the
ring was. In the journal Scanning, the researchers
recount how they used a scanning electron
microscope to investigate the origins of the ring.
Notably, they discovered that the stone in the ring
is actually colored glass – at the time an exotic
material for the Vikings, though it had been made
for thousands of years in the Middle East and
North Africa.
Even more notably, the ring displayed a
remarkable lack of wear, leading the authors to
speculate that it had few – if any – owners in-
between its creator and its Viking owner. Instead,
Wärmländer and his colleagues suggest, it
appears to show direct contact between Viking
society and the Abbasid Caliphate that dominated
much of the Middle East and North Africa. The
authors write, "it is not impossible that the
woman herself, or someone close to her, might
have visited — or even originate from — the
Caliphate or its surrounding regions."
While physical evidence of it is unusual, there
have been plenty of accounts of Scandinavians
from this period crossing paths with the early
Muslim world. By the 11th century Vikings had
become known for their lengthy sea voyages,
journeying as far west as the Americas and likely
reaching Constantinople and even Baghdad when
they traveled the other way. And while
contemporary accounts of Vikings from Western
Europe suggests terrifying invaders, most
accounts suggest the Vikings, likely fearful of the
more sophisticated warriors in the region, instead
looked for trade when they went east.