[Note: Feel free to edit and expand as you please, just don't change the basics. Please correct my terrible Latin if you can. Delete this message when that is done.]
Is the King Catholic?
In Henry the Eighth's attempts to procure an annullment from Pope Julius II are successful thanks to a generous donation to the Vatican treasury. Accordingly, the English King did not take command of the Church of England, remaining a (supposedly) devout Catholic. Other than improved trade and relationships between the Holy See and other Catholic nations, very few changes occur for England proper.
'Seven Years War'
In 1740, new Pope Benedict XIV issued the Papal Bull Discidium Mundus Novus, an edict splitting North America between England and France. Other than the OTL American states owned by Spain, all of the North American continent is included. Quebec, 'Acadia' (OTL Nova Scotia excluding Cape Breton) and New Brunswick, named Acadia Superior, the Louisiana territory, and all unclaimed territory in the Americas in the Mississippi River area is made sovereign French territory. OTL Ontario, Newfoundland and Labrador, Manitoba, Saskatchewan, Alberta, British Colombia, the northern Territories, and the 13 Colonies in 'America', and the unclaimed areas not draining into the Mississippi River, as territory of the British Empire. As a Catholic nation still, the Empire is forced to accept, and the French have no religious reason to object. This prevents a seven years war from ever occurring.
Future of 'Canada' and the 'United States'
In 1775, the 13 Colonies rebel against the British Empire as in OTL, but with additional French support thanks to the proximity of sovereign French territory to the rebellious colonies. The war ends two years sooner, with fewer American casualties and slightly more French casualties.
Without a united, contiguous area, and with Quebec a French entity, the Canadian colonies are unable to form a Confederation in the 1860s. As it were, the provinces are as such: Rupert's Land (the OTL Territories of Yukon, Northwest Territories and Nunavut, and the northern Manitoba) the Province of Buffalo (comprised of OTL provinces of Alberta, Saskatchewan and southern Manitoba, British Columbia