Paul-Henri Charles Spaak (; 25 January 1899 – 31 July 1972) was an influential Belgian Socialist politician, diplomat and statesman who thrice served as the prime minister of Belgium and later as the second secretary general of NATO. Nicknamed "Mr. Europe", he was a leader in the formation of the institutions that evolved into the current European Union, along with Robert Schuman, Alcide De Gasperi and Konrad Adenauer. Wikipedia