It's almost a coffee table book, nicely printed, nicely illustrated, if it was a few inches bigger it would make the coffee table class. The author is, or is writing for, Viking re-enactors or gamers, he doesn't write like an ordinary historian. It reads well, and tells the story of the Vikings the way most histories tell it, you can quote from the book and nobody is going to challenge your ideas. He talks about the famous names, Ragnar Lodbrog, Sven Forkbeard, Hrolf Ganger, Lief Ericsson, Harald Hardrada, Eric Bloodaxe. Nice discussion of things like clothing, farming, the gods of Asgard. I am enough of an amateur historian to have heard of most of the things in the book, but it's a fine introduction for folks unfamiliar with the Viking age.
Dougherty introduces us to the modern Russian historical controversies without taking sides. Viking traders on the way to Constantinople penetrated most of what is now European Russia. It's clear that the Viking culture had influence upon the lands and peoples of Russia. Modern Russian historians are reluctant to allow that Vikings are the founders of Russia. They like to emphasis the native slavic genius and downplay the influence of the Vikings. Since the relevant sites are all deep inside Russia, only available to Russian archeologists, there is little that Western writers can say with much authority.
All in all, a good read. It would be better if they gave some provenance to the numerous and lovely illustrations. They range from photos of ancient rune stones to a nice color illustration that I recognized from National Geographic magazine years ago. Giving the name of the illustrator and a date would add interest to the illustrations.