In the late eighteenth and early nineteenth century, as European trade interests among the Northwest Company and the Hudson's Bay Company expanded into northern Canada, arctic indigenous peoples began to become more involved in the trade process. Increasingly more European goods, including kettles, iron tools, tobacco, alcohol, and guns, were bought and traded by the indigenous peoples within their communities. European imports in exchange for more primitive, native resources and tools made life for the indigenous more efficient and comfortable. Native societies in the early eighteenth century also began to buy guns from European traders, and these guns made hunting easier. They were also occasionally used in native etiquette, medicinal, and religious practices. Because of the natives' increased hunting efficiency, scarcity of resources became an issue in the region, a version of what American human ecologist Garrett Hardin called "the tragedy of the commons."