Two competing waves of migrationto the Laurentians got under wayin the early 1840s, according to historian Serge Laurin. One, says Laurin, wasFrench-Canadian and Catholic, the other wasEnglish-Canadian and Protestant. Both occurred at precisely the same time; both followed different routes. 
French-Canadian migration, larger in scale than the English Protestant wave, proceeded northwards from the old parishes of Terrebone and Deux-Montagnes. At Saint-Jérôme, the movement continued northwards along the North River and into nearby townships. At Sainte-Agathe, it branched off to the east towards Saint-Donat; further north at L'Annonciation, it branched off again, this time in several directions.
While French-Canadians were moving north in large numbers, English Protestants, in smaller but steady numbers, were leaving the older, southern parts of Argenteuil County. They began to move northwest from Lachute and Brownsburg, into the townships of Grenville, Harrington, Wentworth, and Arundel. They then moved eastward into Morin township, where theycame into contact with the ongoing northward progression of French Catholics. In the 1860s, says Laurin, the two movements finally met one another around the confluence of the Rouge River and its tributary, the Diable, in de Salaberry township. And it was around that time (1868) that Curé Antoine Labelle arrived in Saint-Jérôme. It was Labelle who championed most actively the cause of French Catholic colonization of the Laurentians. And it was Labelle who would insure that the bulk of the region would be colonized by French-Canadians.Reference:Serge Laurin, Histoire des Laurentides, 1989.