In 1325, soldiers from Modena snuck into the city of Bologna in the middle of the night and stole a wooden bucket from a well. Bologna declared war. Two thousand men died. The bucket is still in Modena. Bologna has never gotten it back.

That is the legend. The truth is messier, bloodier, and in some ways more interesting. Behind the bucket were two hundred years of accumulated grievance between two rival Italian city-states, the grinding factional violence of the Guelph and Ghibelline conflict, and a battle in which a seven-thousand-man Modenese force defeated a Bolognese army more than four times its size—then held a celebratory race outside the walls of the city they had just humiliated.

Host Shawn Spainhour takes you into the full story: the specific mechanics of how medieval Italian city-states fought and why they could never stop ...