Chicago’s first pizzeria, Granato’s, opened in 1924 on Taylor Street, but pizza did not become popular among the local masses until the early ’40s, after the end of Prohibition. It was served mostly in taverns, often as an enticement to drink alcohol. Possibly because taverns were not usually equipped with silverware or plates, the owners sliced the pizza into little squares, which could be set on napkins.

Chicagoans were less beholden to Old World traditions than were New Yorkers, who hand-tossed their dough, just like their forebears in Italy. Chicago tavern owners rolled theirs, eventually leading to the use of mechanical sheeters. The machines were faster and more economical and also produced a thinner crust.

“Savvy bar owners realized they could make ultra-thin pizzas for cheap, cut their pies into tiny squares, and then pass the bite-sized snacks around,” writes Steve Dolinsky in The Ultimate Chicago Pizza Guide: A History of Squares and Slices in the Windy City. “The goal was to get something salty into the customers’ mouths so they’d order more beer.”

So the next time you eat Chicago’s version of thin crust, wash it down with a pour. That’s how it was intended.

Send your questions about the Chicago area to emcclelland@chicagomag.com.