The Louisiana Purchase<span> (1803) was a land deal between the </span>United States<span> and France, in which the </span>U.S. acquired<span> approximately 827,000 square miles of land west of the Mississippi River for $15 million.</span>
The event that set off World War I was the assassination of Archduke Franz Ferdinand of the Austro-Hungarian Empire and his wife Sophie by Gavrilo Princip, a Serbian nationalist, on June 28, 1914 in Sarajevo.
