Pretty long time spans. There are a lot of forests where fires are not part of the life cycle.

Large scale forest fires have never been a large part of the lifecycle of the moist northeast. That might change, but around the great lakes region at least our forest type is entirely different than the western half of the continent. Rain is fairly consistent here.

The first nations did practice controlled burns for the sake of wildlife management (to increase open grazing land) for sure, and smaller scale forest fires did/do happen. But nothing like out west.

Some. Not most.