During World War I, Japan officially declared war on Germany.
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A German U-Boat sinks the RMS Lusitania.
Medical researcher Oswald Hope Robertson performed the first-ever blood transfusion using stored and refrigerated blood.
The United States of America declared neutrality at the beginning of World War I.
The Red Baron is killed.
During WWI, The Battle of Gallipoli concluded with an Ottoman Empire victory when the last Allied forces were evacuated from the Peninsula.
