It is important to note that New Orleans was and remains a port for international trade. People come and go from all parts of the globe. It is a hodgepodge of cultures, classes, ideas, and languages. Despite the many laws against it, the mixing of people and culture did happen.
The conditions in which people lived under slavery were abominable. Because of Catholicism, these people had one day of rest per week. They used this time to grow their own crops, which they would sell to the free and slave alike in the market square. Some would hire themselves out for money. Despite their horrible circumstances, these people managed to preserve their African heritage and culture.
Congo Square is a symbol of determination and resilience.
It is also the place from which American music was transformed.

By fred - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=108577425