They didn’t see it coming, because they were looking the other way:

Speaking of wildfires, my book of the day is Under a Flaming Sky: The Great Hinckley Firestorm of 1894. It is the sharply written story of a how a Minnesota town of 1,200 was devastated by a catastrophic firestorm that came raging out of the nearby woods with tornado-class winds and a 300-foot wall of fire, killing 436 people.

— Book du Jour: Under a Flaming Sky, Paul Kedrosky, Infectuous Greed, October 3, 2007

Wikipedia says it burned 200,000 acres and some sources say 800 people died. Some people who lived jumped into wells or ponds or the river, or caught one of two trains that made it out of town.

So what was it that burned?