By Adam Taylor March 18, 2015 Follow @mradamtaylor (Statens historiska museum / Christer Ahlin) In the modern-era, 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...