Medical researcher Oswald Hope Robertson performed the first-ever blood transfusion using stored and refrigerated blood.
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The US National Advisory Committee for Aeronautics was founded as an emergency measure during WWI.
During World War I, as a soldier, Adolf Hitler was injured by a grenade blast.
The Treaty of Lausanne is signed between Turkey and the countries that formed the Allied Powers in the First World War.
The First Battle of the Marne began during World War I.
The Treaty of Versailles takes effect.