John A. Macdonald was a huge promoter of Confederation and even made an alliance with his political rival, George Brown to make it happen.
This approximated the political dichotomy that existed prior to Confederation although, because of the realignment, some former Liberals became Conservatives and vice versa.
The acceptance of the Confederation Party was greatly influenced by the American Civil War.
Other reasons were an aggressive American foreign policy and the Fenian Raids of 1866.
It was also feared that the French-Canadian interests would be weakened if the Confederation was embraced in Canada East (modern-day Quebec).