when did the us get the ohio river valley
Ohio River The 1768 Treaty of Fort Stanwix opened Kentucky to colonial settlement and established the Ohio River as a southern boundary for American Indian territory.[10] In 1774, the Quebec Act restored the land east of the Mississippi River and north of the Ohio River to Quebec, in effect making the Ohio the southern boundary of Canada. This appeased the Canadien British subjects but angered the Thirteen Colonies. Lord Dunmore's War south of the Ohio river also contributed to giving the land north to Quebec to stop further encroachment of the British colonials on native land. During the American Revolution, in 1776 the British military engineer John MontrÃ©sor created a map of the river showing the strategic location of Fort Pitt, including specific navigational information about the Ohio River's rapids and tributaries in that area.[11] However, the Treaty of Paris (1783) gave the entire Ohio Valley to the United States.
Mississippi River The Mississippi River is called the Lower Mississippi River from its confluence with the Ohio River to its mouth at the Gulf of Mexico, a distance of about 1,000 miles (1,600 km). At the confluence of the Ohio and the Middle Mississippi, the long-term mean discharge of the Ohio at Cairo, Illinois is 281,500 cubic feet per second (7,970 cubic metres per second),[23] while the long-term mean discharge of the Mississippi at Thebes, Illinois (just upriver from Cairo) is 208,200 cu ft/s (5,900 m3/s).[24] Thus, by volume, the main branch of the Mississippi River system at Cairo can be considered to be the Ohio River (and the Allegheny River further upstream), rather than the Middle Mississippi.