For sixty years after Lewis and Clark returned from their expedition, the headwaters of the Yellowstone remained unexplored except by the trader and trapper. The traffic in peltries it was that first induced extensive exploration of the west. Concerning the precious metals, the people seem to have had little faith in their abundant existence in the west, and no organized search for them was made in the earlier years of the century. But that country, even in its unsettled state, had other and important sources of wealth. Myriads of beaver inhabited the streams and innumerable buffalo roamed the valleys. The buffalo furnished the trapper with means of subsistence, and beaver furs were better than mines of gold. Far in advance of the tide of settlement the lonely trapper, and after him the trader, penetrated the unknown west. Gradually the enterprise of individuals crystallized around a few important nuclei and there grew up those great fur-trading companies which for many years exercised a kind of paternal sway over the Indians and the scarcely more civilized trappers. A brief resumé of the history of these companies will show how important a place they occupy in the early history of the Upper Yellowstone. The climax of the western fur business may be placed at about the year 1830. At that time three great companies operated in territories whose converging lines of separation centered in the region about Yellowstone Lake. The oldest and most important of them, and the one destined to outlive the others, was the world-renowned Hudson's Bay Company. It was at that time more than a century and a half old. Its earlier history was in marked contrast with that of later years. Secure in the monopoly which its extensive charter rights guaranteed, it had been content with substantial profits and had never pushed its business far into new territory nor managed it with aggressive vigor. It was not until forced to action by the encroachments of a dangerous rival, that it became the prodigious power of later times. This rival was the great North-west Fur Company of Montreal: It had grown up since the French and Indian War, partly as a result of that conflict, and finally took corporate form in 1787. It had none of the important territorial rights of the Hudson's Bay Company, but its lack of monopoly was more than made up by the enterprise of its promoters. With its bands of Canadian frontiersmen, it boldly penetrated the north-west and paid little respect to those territorial rights which its venerable rival was powerless to enforce. It rapidly extended its operations far into the unexplored interior. Lewis and Clark found its traders among the Mandans in 1804. In 1811 the Astorians saw its first party descend the Columbia to the sea. Two years later the American traders on the Pacific Coast were forced to succumb to their British rivals.