Fur trade marten furs could generate in international markets spurred a "fur fever" in which many Russians moved to Siberia as independent trappers. From 1585 to 1680, tens of thousands of sable and other valuable pelts were obtained in Siberia each year. The primary way for the Muscovite state to obtain furs was by exacting a fur tribute from the Siberian natives, called a "yasak". "Yasak" was usually a fixed number of sable pelts which every male tribe member who was at least fifteen years old had to supply to Russian officials. Officials enforced "yasak" through coercion and by taking hostages, usually
Fur of certain furs to the higher social statuses, thereby establishing a cachet based on exclusivity. Furs such as marten, grey squirrel and ermine were reserved for the aristocracy, while fox, hare and beaver clothed the middle, and goat, wolf and sheepskin the lower. Fur was primarily used for visible linings, with species varied by season within social classes. Furbearing animals decreased in West Europe and began to be imported from the Middle East and Russia. As new kinds of fur entered Europe, other uses were made with fur other than clothing. Beaver was most desired but used to make hats