The person who claimed land in the Ohio Valley for France was Pierre Joseph Celoron.
Pierre Joseph Celoron was a French officer of marine and explorer who was also known as Celoron de Blainville. He was born in Montreal, Canada, on December 29, 1693.
In 1749 he took possession of the Valley of Ohio in the name of the king of France. After his return, his was promoted to Major
He died at Montreal on April 12th, 1759.