Before the days of hard top roads, indeed, even before there were roads, the Mississagi River played an important role as a transportation route for both natives and Europeans. Since then the river has become unessential for transportation, but important as a source of hydroelectric power. Thus, the Mississagi River dominates the lives of those who inhabit its valley.

The settlements in the Mississagi Valley are representative of the growth and (sometimes) demise of many Northern Ontario communities. Being rather remote, most of Northern Ontario wasn't settled until the later decades of the nineteenth century. The towns in the vicinity of the Mississagi River Valley, such as Blind River, Iron Bridge, Bruce Mines, and Thessalon were founded in the 1870's. This was in reaction to government promotion of Northern Ontario as the new frontier. Such promotion doesn't seem to have lured many from the Old Country, but many people did leave Southern Ontario, which was becoming increasingly crowded.

The history of the Mississagi River Valley is dominated by the nature of the area. This is because the natural environment dictated the type of industry that could succeed in the region. And, as this section demonstrates, industry is an important factor in the history of the Mississagi River Valley settlements.