The summer of 1871 was dry. About one inch of rain had fallen in 4 months. On October 8th the city on Lake Michigan was about to endure one of the
worst urban fires in American history. Maximizing tinder-dry conditions, a gale-force wind turned a small fire into a huge disaster. Almost three square miles of the city were destroyed. Nearly 300 people died. The entire business section was wiped out.
Chicago had come a long way since John Kinzie
built the
first house there in 1815. From a small settlement, not far from
Fort
Dearborn, to a growing transportation center 40 years later, Chicago prospered. As the Civil War neared its end, Chicago was "the metropolis of the northwest."
The three branches of the Chicago River formed a kind of boundary for the town (as demonstrated by this link to an 1871 Harper’s Weekly drawing). The south branch (left side of the picture) divided the rural part of south Chicago (where the O’Leary family lived) from the urban part.
In 1871, Chicago had over 330,000 inhabitants. Its fire department and equipment were modern for the time, but the city employed only 185 fire-fighting personnel.
On the night of October 7th, a mill plant fire broke out at 209 Canal Street. Some of the city’s equipment was damaged while firemen were battling that blaze. Worse, the mill fire overtaxed an already overworked, understaffed fire-fighting crew.