 The French and Indian War erupted when territorial disputes between France and Great Britain in North America reached a head in 1754 . By 1763 , France was defeated by the much greater strength of the British army and was forced to cede its Canadian possessions to the English and Louisiana to the Spanish in the Treaty of Paris , amounting to most of its colonial holdings in North America . Initially , the Spanish did not extensively explore the Missouri and let French traders continue their activities under license . However , this ended after news of the British Hudson 's Bay Company incursions in the upper Missouri River watershed was brought back following an expedition by Jacques D <unk> in the early <unk> . In 1795 the Spanish chartered the Company of <unk> and <unk> of the Missouri , popularly referred to as the " Missouri Company " , and offered a reward for the first person to reach the Pacific Ocean via the Missouri . In 1794 and 1795 expeditions led by Jean Baptiste <unk> and Antoine Simon <unk> de la <unk> did not even make it as far north as the Mandan villages in central North Dakota . 
