New France
New France () was the area colonized by France in North America during a period beginning with the exploration of the Gulf of Saint Lawrence by Jacques Cartier in 1534 and ending with the cession of New France to Great Britain and Spain in 1763 under the Treaty of Paris (1763).
Three Flags Day
France had ruled Louisiana from its founding until the Treaty of Paris (1763) which ended the Seven Years' War (whose North American phase was the French and Indian War), in which treaty Spain received the French land west of the Mississippi River (the "right bank" going downstream) plus New Orleans, and Great Britain received the French lands east of the River (the "left bank") -- which included what had previously been called the Illinois Country or "Upper Louisiana".