The first was a military one. Instead of capturing Nova Scotia (which was largely sympathetic to the American cause) and preventing British reinforcements from getting up the St. Lawrence to Montreal and Quebec, the Americans decided to make simultaneous attacks on the two cities. Montreal fell relatively easily, but Arnold failed to capture Quebec.
The other mistake the Americans made was one of politics, or perhaps “public relations.” Although they invited Canada and Nova Scotia to join the union, they did not send emissaries soon enough to try personal sales appeals. It was April 1776, before Benjamin Franklin led a carefully chosen delegation to Montreal, which had already been captured. It arrived on April 29, and included Charles Carroll and his cousin John, two eminent Catholics who were supposed to persuade Roman Catholic leaders in Quebec that their church would have as much freedom in an American State as it had under British rule. Canadian church leaders were not impressed. In fact, they disciplined a Montreal priest who allowed John Carroll to celebrate mass.
There were a number of American businessmen living in Montreal who had gone there from New York when Britain took Canada from France. They were heartily disliked by Governor Murray, the first British military governor of Quebec. He called them “licentious fanatics trading here.” They, and some of the Canadian businessmen in Montreal, gave the Franklin commission a warm welcome, but generally speaking, the reception from most people was cold.
The Americans brought a good supply of “Continental dollars” to pay their bills, but even the cab drivers refused to accept them. The expression “not worth a continental damn,” sometimes heard even today, originated from the Continental dollars.
The Franklin delegation was too late. One week after it arrived in Montreal, British warships began arriving at Quebec. When the Americans fled from there, Franklin led his party back to Philadelphia for the signing of the Declaration of Independence. It was then that Franklin made his famous quip. One of the signers said: “We must all hang together.” Franklin quickly added: “Or we shall all hang singly.”
I can tell you want to learn more about Benjamin Franklin and how he almost convinced us all the American way! There’s the usual suspects such as Wikipedia, an extension to the story at The Gazette, you can read an interesting timeline post at Counter-Factual.net by WestVirginiaRebel.
For those of us who like to hold a book in our hands, there are a few to choose from. The Invasion of Canada in 1775, Canada and the American Revolution, 1774-1783, and The Fall of New France: How the French lost a North American empire 1754-1763.