On March 19, 1687, Robert de La Salle was murdered by Pierre Duhaut during a mutiny while searching for the mouth of the Mississippi River.
La Salle left France in 1864 with four ships and 300 colonists in an attempt to establish a French colony on the Gulf of Mexico, at the mouth of the Mississippi River. However, the journey was ill-fated and plagued by pirates, hostile natives and poor navigation almost from the beginning.
After running one of his final ships aground near Navasota, Texas, the remaining 36 men led a mutiny and murdered Robert de La Salle.
On February 20, 1792, President Washington formally created the U.S. Postal Service with the signing of the Postal Service Act, which outlined in detail Congressional power to establish official mail routes. The act allowed for newspapers to be included in mail deliveries and made it illegal for postal officials to open anyone's mail.