France
under French rule until 1803, when all the French territory west of the Mississippi River was purchased by the United States.i.e. it was first claimed by France .
I don't know the first but La Salle was the who claimed it.
Rene-Robert de LaSalle was a French explorer.Just look him up on Google. hope i helped and if i did pleaze get mad at me.i am crazy!!!honestly !!! Robert LaSalle was an explorer and he traveled for the country France.LaSalle sailed from the 1670's-1682 he claimed the Mississippi river and the other places along the river.
the people who almost found the Mississippi river is Jacques marquette and Lois jolliet they tured around because they were afraid they would see spanish soldiors but the real man who fund the mouth of the Mississippi river is..............idk go to Google and ask (: have a nice day
Hernando De Soto was the first known European Explorer in Mississippi. Sieur de La Salle a French explorer was the first to travel down the Mississippi River in 1682. La Salle claimed the Mississippi Valley for France on April 9, 1682.
Hernando De Soto claimed nothing. He was the first European to see the Mississippi river.
French explorer Rene-Robert Cavelier, Sieur de La Salle was the first to explore the length of the Mississippi River. He named the basin Louisiana and claimed it on April 9, 1682 for France.
The Mississippi River was first discovered and explored by Hernando DeSoto, who was a Spanish explorer.
the Mississippi river
Spain originally claimed the land west of the Mississippi. However, Russia claimed Alaska and some of the west coast. Mexico had won independence from Spain in 1810. Then Napoleon of France conquered Spain and all of its lands.
Pike's first exploration followed the Mississippi River.