French explorers first celebrated Mardi Gras in Louisiana in 1699. The event took place during Pierre Le Moyne d’Iberville’s expedition near the mouth of the Mississippi River.
The expedition reached the river on March 2, 1699, and proceeded upstream to a campsite in what is now Plaquemines Parish, roughly 60 miles downriver from present-day New Orleans. The next day, March 3, was Mardi Gras, so d’Iberville named the location Point du Mardi Gras and a nearby waterway Bayou Mardi Gras.
The explorers were observing a French Catholic festival before Lent, not staging the large parades associated with modern New Orleans. Those later traditions developed over many generations. French settlers established an organized Mardi Gras tradition in Mobile in 1703, while New Orleans was founded in 1718 and became Louisiana’s capital in 1723.
A frequent mistake is answering 1718, the year New Orleans was founded, or 1703, the year of Mobile’s early organized celebration. The question asks about the first French colonial observance in Louisiana, which dates to 1699.