the 1840s, new views about empire emerged in Great Britain.
Known as “Little Englandism”, this view considered colonies not
as commercial assets, but as liabilities. It came from the
economists of the School of Manchester who viewed free trade as
more efficient and profitable than the old mercantile system in
place since the 16th century.
Little by little, under the growing influence of thinkers
from the School of Manchester, mercantilism was abandoned in
favor of free trade, until the Corn Laws were repealed in
1846 and the Navigation Laws in 1849, putting an end to
preferential duties for the colonies.
Britain's new policy had major economic and political
consequences for BNA. The abandonment of the mercantile system
was felt to be a betrayal, especially by the Canadian merchants
who were losing their advantages on the British market. As a
result, some British merchants of Montreal launched a movement
for the annexation of Canada to the US. While this particular
movement was short-lived, the end of preferential duties for the
colonies encouraged a realignment of BNA trade towards the
United States. A Reciprocity Treaty with the US that introduced
free trade for natural products was signed in 1854, and in the
1850s BNA exports to the US were multiplied by 4.