So, this happened today, in New Orleans, Louisiana. I love New Orleans! It would have been great fun to have been there!
Back of card says: Mardi Gras, or Fat Tuesday, is the final day of Carnival, which begins on the Feast of the Epiphany, January 6. Made a Christian holiday by Pope Gregory XIII when, in 1582, he put it on the Gregorian calendar (the 12-month one we still use today). He placed Mardi Gras on the day before Ash Wednesday, the first day of Lent. That way, all the debauchery would be finished when it came time to fast and pray.