Spears, swords, and the dreaded skeggox, or battle-axe, was amongst Viking equipment, but the large number of scales, measuring weights, goods markers, and other trading paraphernalia is testimony to more standard commercial routes to riches.  Trade and barter was never far from their minds. They came late to the concept of coinage, the oldest known coin being minted in Hedeby in the early 9th century. Their silver jewellery was always made to weight, for ease in trading; and many arm-rings uncoiled for part of their length and hacked off and sold when the wearer needed ready silver. Their homelands provided the furs, falcons, amber, walrus ivory, timber, and good-quality iron ore that earned them the gold, silver, glass work, and other foreign luxuries they craved.  

Seeing the human, familiar side of one's enemy is rarely comfortable, as Ceridwen and Ælfwyn find out.  Danes who were law-abiding family men at home took ship and became rapacious pillagers.  Opportunism must have played part in this - Scandinavian traders may have been tempted beyond their limits by unprotected villages in their travels.  Raiding became easier than trading.