The Irish colonized many areas behind the long-settled French communities lining the St. Lawrence River. They were especially prominent north and south of Montreal and north and south of Quebec City.
Settling on rented seigneurial land and sharing their lives with people who spoke a different language from theirs and in many cases followed a different religion, they formed extensive Irish communities of mixed religion across the region. Most were farmers, though some supplemented their incomes with seasonal employment in the lumber camps to make ends meet.
With the opening up of colonization roads the Irish became well concentrated in the Eastern Townships - especially in the St. Francis Valley.
By 1851 Quebec's Irish immigrant population was twice that of the English and Scottish immigrant populations combined. One third of the Irish lived in Montreal and Quebec City while the remainder were mainly concentrated in the farming districts of the Upper Ottawa Valley, the Beauharnois region, south of Montreal and the Eastern Townships.