In Decades of Darkness, the War of 1811 and later events affected much of Canada, being British territory, it was aligned with the Republic of New England and was closely aligned to it in the following years. The Americans* tried an invasion of the colony led by Major General Thomas Pinckney, but after losing control of Lac Erie and other military defeats, Americans* are forced to withdraw. USA* through the conflict loses its hold on the Indiana Territory because of British and natives, in the following years settlers from both New England and from the two Canadas settle in it, Detroit falling under British control.
At the same times, New Brunswick, Nova Scotia and Prince Edward Island steadily moves toward becoming part of New England.
Then came the War of 1833, starts with Americans* success due to the British forces being occupied with Irish revolts. By the end of the war, British forces manage to control the Great Lakes regions. During the post-war negociations, U.S.A* is force to abandoned claims over the North-East. Wisconsin and the upper peninsula of Michigan are therefore incorporated as British territory. The city of Dearborn stand now where is Chicago.
Like OTL, Canada was hit by uprising against British Rule in 1836, they follow a similar path as OTL and are quickly put down. However, in the post-war period the two provinces remains separated. However, the two wars and larger immigration (USA* being less popular with them) strengthen Canadian nationalism. Britain opt to give their the core of their North American colonies internal autonomy, but to control its external policy. The youngest brother of King Edward VII becomes James I, King of Canada.
Nephites (DoD verson of the Mormons), decides to settle themselves in Wisconsin and Western Canada around the time of the creation of the kingdom. In the aftermath of the war, negotiation between British and Americans* over the frontier turn differently, the 46th parallel is set as a frontier rather than the 49th, making Canada larger (the territory of OTL state of Washington is included in Canada).
The war between the Ottoman Empire and Russia, in which Britain fought against Russia led to Canadian occupation of Alaska in 1858. It is annexed in 1864. In 1866, Métis revolt under the guidance of Louis Dumont over and the rising number of immigrants taking their lands. Irish also take part in the rebellions as they oppose the pro-British rule of the King. Militias are unable to put down the rebellion and so the army is called. Pro-Métis sentiment is present in Quebec, while Ontario want retribution. James I steps in to settle the issues, dissolving Wisconsin provincial legislature, the establishment of a new provincial government of Manitoba, and guaranteed protection for the religious and language rights of the Catholics in both Wisconsin and Manitoba. The rebels calm down with the concession. Nephites after the rebellion leave Wisconsin to the Vancouver island. Canada was part of the Second Napoleonic War with its traditional allies.
*Sir Isaac Brock, while a major Canadian military figure OTL was wounded during the war of 1811, made prisoner and died in obscurity
*James Henry Craig as governor of Canada OTL, created several measures that enforced English rule in French speaking lower Canada, however the war of 1811 stopped theses reform and he died in 1812
*Thomas Douglas founded the red river colony, getting much more interest from local authority, Winnipeg is name Selkirk in his honor
*James FitzGibbon fought in both the War of 1811 and the one 1833
*William Lyon Mackenzie took part in the 1836 rebellion, exiled himself a few years and came back as a political opponoment of King James I, Louis-Joseph Papineau followed a similar path however he moved to New Brunswick after a few years around the world after the rebellion and pressured the Maritimes to join New England
*Louis Riel fought as a Canadian general in the Noth American War
*The success of the Kingdom of Canada led to the extension of the idea to other part of the British empire, such as Ireland, Australia and South Africa