I'm looking at starting a timeline, so I have some questions: could the Fortress of Louisbourg have held against British attacks in the French and Indian/Seven Years War until peace was forced in Europe? Louisbourg repulsed an attack in 1757, so perhaps more ships of the line reach the harbor to assist in the defence? And if it is possible, how much of France's colonial empire could be retained, and what butterflies could be seen in the European theater?