Immigration in the 18th Century

I am wondering what might have been the main reason for immigration in America (Canada especially) during the 18th Century. I have an ancestor born in Trondheim in 1752 who was married in Quebec City in 1794 to a French woman. Where there norwegians involved in any way during the American Revolution? Was there significant commercial exchange between Norway and Canada at that time? This man seemed to be acquainted with ships, his marriage contract says he was a pilot....