QUICK The Ohio River has had the most impact on the nation's history.

It wasn't the biggest but i'd say it was close. The Ohio River was the cause of the 7 years war which is also called The French & Indian War which was a huge war between France, The colonists, and the British Crown. The reason it was called the French & Indian war is because the Indians helped the French fight. I believe British won that war.

Explanation:

world war i began in 1914, after the assassination of archduke franz ferdinand, and lasted until 1918. during the conflict, germany, austria-hungary, bulgaria and the ottoman empire (the central powers) fought against great britain, france, russia, italy, romania, japan and the united states (the allied powers). to new military technologies and the horrors of trench warfare, world war i saw unprecedented levels of carnage and destruction. by the time the war was over and the allied powers claimed victory, more than 16 million people—soldiers and civilians alike—were dead.

explanation: