The last conflict between Canada and a neighbour (not a rebellion or a conflict vs. natives) was the 1812 war which ended in 1815, more than 2 centuries ago.
The last conflict between the US and a northern neighbour was that 1812 war. In the south it was the Mexican-American war which ended in 1848, 175 years ago.
Internal rebellions, civil wars, and guerilla conflicts don’t count as conflicts with neighbours.
The last conflict between Canada and a neighbour (not a rebellion or a conflict vs. natives) was the 1812 war which ended in 1815, more than 2 centuries ago.
The last conflict between the US and a northern neighbour was that 1812 war. In the south it was the Mexican-American war which ended in 1848, 175 years ago.
Internal rebellions, civil wars, and guerilla conflicts don’t count as conflicts with neighbours.