River Kings: The Vikings from Scandinavia to the Silk Roads, by Cat Jarman
A really interesting look at the Viking age, essentially tracing the route of an amber bead found in a Viking grave in Repton all the way back to its likely source in India, with lots and lots and lots of interesting diversions along the way. The real million kroner question is: did those goods make their way gradually, over time, through trade, with multiple owners; or, did they make it all in two or three great leaps and bounds, along with the same person or two or three? The answer seems to be: yes. Vikings did so much trade with the Islamic caliphate that their currency systems were linked, and in a Stockholm museum is a small Buddha taken from a Viking dig.