who discovered the mississippi river?

Although the Mississippi river was discovered in its lower course by Hernando de Soto in 1541, and possibly by Alonso Alvarez de Pineda in 1519, Europeans were not yet prepared to use the discovery, and two Frenchmen, Louis Joliet and Father Jacques Marquette, first made it generally known to the civilized world by a voyage down the river from the mouth of the Wisconsin to the mouth of the Arkansas in 1673.i In 1680 Louis Hennepin, sent by La Salle, who planned to acquire for France the entire basin drained by the great river and its tributaries, explored the river from the mouth of the Illinois to the Falls of St Anthony, where the city of Minneapolis now stands, and two years later La Salle himself descended from the mouth of the Illinois to the Gulf, named the basin Louisiana, and took formal possession of it in the name of his king, Louis XIV. By the war which terminated (1763) in the Treaty of Paris, Great Britain wrested from France all that part of the basin lying east of the middle of the river (except the island of New Orleans at its mouth), together with equal rights of navigation; and the remainder of the basin France had secretly ceded to Spain in 1762. During the War of Independence the right to navigate the river became a troublesome question. In 779 the Continental Congress sent John Jay to Spain to negotiate a treaty of commerce, and to insist on the free navigation of the Mississippi, but the Spanish government refused to entertain such a proposition, and new instructions that he might forego that right south of 31 N. latitude reached him too late. While the commissioners from Great Britain and the United States were negotiating a treaty of peace at Paris, Spain, apparently supported by France, sought to prevent the extension of the western boundary of the United States to the Mississippi, but was unsuccessful, and the United States acquired title in 1783 to all that portion of the basin east of the middleof the river and north of 31 N. lat. In 1785 Congress appointed John Jay to negotiate a commercial treaty with Don Diego de Gardoqui, the Spanish minister to the United States, but the negotiations resulted in nothing. For the next ten years the Spaniards imposed heavy burdens on the American commerce down the Mississippi, but in 1794 James Monroe, the United States minister to France, procured the aid of the French government in further negotiations, for which Thomas Pinckney had been appointed envoy extraordinary, and in 1795 Pinckney negotiated a treaty which granted to the United States the free navigation of the river from its source to the Gulf and the privilege of depositing American merchandise at the port of New Orleans or at some other convenient place on the banks. Spain retroceded Louisiana to France in 1800, but the Louisiana Purchase in 1803 left very little of the Mississippi basin outside of the United States.

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