object in giving this order, however, was to get citizens for his towns, and thereby encourage commerce and peaceful occupations. Many of the thralls were artisans, and a large number of those who had been enthralled as prisoners of war were men of intelligence and enterprise. Commerce had, even previous to the reign of Olaf the Quiet, enjoyed periods of prosperity. The vikings were often merchants as well as pirates, and bought for money or goods what they could not take with the sword. Merchants, on the other hand, who were not vikings, had always to have the sword at hand to defend their cargoes. A very sharp distinction between the warrior caste and that of the merchants, did not therefore exist, and we find that great chieftains, nay even kings themselves, engaged in commerce, and were not ashamed of the profit they reaped by mercantile enterprise. Thus we hear that Olaf the Saint went into partnership, for one voyage, with the merchant Gudleik Gerdske, and Harold Hard-ruler made the trade with the Finns a royal monopoly which he farmed out to his underlings. A considerable exchange of commodities by barter took place between Norway and Denmark, Sweden and England, and as piracy declined, and the precious metals came into general use, a more regular commercial intercourse. These first effects of a more orderly social organization were beginning to be visible during the reign of Olaf the Quiet, and it is owing to this fact, that we hear so much about the promotion of commerce and the prosperity of the towns. The city of Björgvin (now Bergen) was founded by him (1070-1075) and very soon became a commercial centre of great importance. [Illustration: INTERIOR OF ORKHAUGEN, OLD NORSE DWELLING ON THE ORKNEYS.]