Origins
Literally meaning "Fat Tuesday," Mardi Gras is the culmination of a weeks-long Carnival season that ends on Ash Wednesday. While impromptu foot and horseback parades had been a regular New Orleans occurrence for decades, it was in 1857 that the first "krewe" — private groups with semi-mythological namesakes that organize thematic parades — was established. This 1879 picture details a parade by Rex, an all-male krewe whose leader is known as the "King of Carnival." The Krewe of Rex established the official Mardi Gras colors of green, gold, and purple.

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