Medical researcher Oswald Hope Robertson performed the first-ever blood transfusion using stored and refrigerated blood.
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The Julian Calendar was used for the first time.
Portuguese navigators discovered Rio de Janeiro.
Fidel Castro's revolutionary forces overthrew the Cuban dictator Fulgencio Batista.
A Scandinavian research collaboration created the first-ever internet domain name Nordu.net.
The Euro currency was introduced and adopted by 11 Member States.