A 2.7-acre patch of dirt in New Orleans' Treme neighborhood was designed as a containment tool. This episode traces how Congo Square backfired on the authorities who created it. Under the 1724 Code Noir, enslaved Africans were granted Sundays off but forbidden to congregate, so gatherings scattered to levees and a clearing on Bayou St. John. In 1817 the mayor forced them into a single monitored location. Instead of neutralizing a threat, the concentration let diverse African traditions combine into what the hosts call an unstoppable engine for cultural resistance, economic survival and musical innovation.

We look at the Sunday market where people sold goods grown, trapped or crafted in their few off hours, keeping the profits under lingering Spanish legal traditions and saving to purchase their own freedom through coartacion. Architect Benj ...