Significant Events An "event" is something that happens, something that takes place in time. An historical event is something that affects many people in an important way. The significance of an event cannot be measured scientifically. Every historian, journalist or student could make their own top ten or one hundred lists. This selection is meant to draw attention to 100 events in Canadian history that left an indelible mark on the lives of the people of the time and an indisputable memory in the minds of later generations.