You'd probably want to have a look at Ethan Allen and the Green Mountain Boys. They were involved on the American side at Fort Tinconderoga and Montreal in the early stages of the war before Ethan Allen was captured by the British. While he was in captivity, Vermont declared independence of both the United States and Great Britain. When Allen returned from British imprisonment he then entered into discussions with the British to bring Vermont into Canada and and into the war on the British side. Ultimately nothing came of these discussions because the war came to an end but Allen seemed amenable to the idea of joining Britain.

Throughout the war Vermont was very much on it's own idea due to an ongoing dispute with New York, which claimed the entire area, thus Vermont didn't join the United States until as late as 1791 even though it was somewhat settled during the Revolutionary War and played an active role.