The direct cause of WWI was the assassination of Archduke Franz Ferdinand at Sarajevo on 28 June 1914. However historians feel that a number of factors contributed to the rivalry between the Great powers that allowed war on such a wide-scale to break out.
Answer: The black plague killed hundreds of thousands very quickly with no cure
Explanation:
Washington served as a general and commander-in-chief of the colonial armies during the American Revolution, and later became the first president of the United States, serving from 1789 to 1797