Six years later, in 1615, Champlain set out on his most important tour of western discovery, largely for the purpose of fulfilling a promise made to one of his lieutenants on the upper Ottawa to assist him in the continual quarrel between the Hurons to the northward and the Iroquois. Here again is forced upon our attention one of the most important sequences of the battle of Lake Champlain. The two routes to the Great Lakes of Montreal were by the St. Lawrence River and by the Ottawa River. Either route the voyage was long and difficult, but by the Ottawa the voyageur came into the "back door" of the Lakes, Georgian Bay, by a taxing portage route; while, once stemming the St. Lawrence, Lake Ontario was gained and, with the Niagara portage accomplished the traveller was afloat on Lake Erie beyond which the waterway lay fair and clear to the remotest corner of Superior. But the St. Lawrence led into the Iroquois frontier, and the Ottawa to the country of the French allies, the Hurons. The result was that, to a great extent, French movement followed the northerly course; no one could bring this out more clearly than Hinsdale and those whom he quotes: [The Iroquois] turned the Frenchmen aside from the St. Lawrence and the Lower Lakes to the Ottawa and Nipissing; they ruined the fur trade "which was the life-blood of New France"; they "made all her early years a misery and a terror"; they retarded the growth of Absolutism until Liberty was equal to the final struggle; and they influence our national history to this day, since "populations formed in the ideas and habits of a feudal monarchy, and controlled by a hierarchy profoundly hostile to freedom of thought, would have remained a hindrance and a stumbling-block in the way of that majestic experiment of which America is the field."[18] Two insignificant historical facts illustrate this power exerted on westward movement from Canada: Lake Erie was not discovered until half a century after Lake Superior, in fact was practically unknown even for fifty years after Detroit was founded in 1701. From the rendezvous in the Huron country this second army of invasion, at the head of which rode Champlain, set out for the Iroquois land, to carry fire and sword to the homes of the enemy and forge so much the more firmly the chains of prejudice and hatred. Crossing Lake Ontario at its western extremity the march was taken up from a point near Sacketts Harbour for the Onondaga fort, which was located, probably, a few miles south of Lake Oneida. The importance of the campaign on the Niagara frontier history is sufficient for us to include again Champlain's account of it: