Jan Masaryk, a diplomat and the longest serving Minister of Foreign Affairs was the son of the first president and founder of Czechoslovakia Tomas Garrigue Masaryk and his American-born wife Charlotte Garrigue.

After independent Czechoslovakia was created in 1918, Jan Masaryk entered its diplomatic service. In 1919, he became the Czechoslovakia's first charge d'affaires in the United States and in 1925, he was appointed ambassador to the Great Britain. In protest against the 1939 Munich Agreement, Masaryk left the diplomatic service and in 1940, he became the foreign minister of the London-based Czechoslovak government in exile. On the eve of the Nazi invasion of Poland, Masaryk spoke out about the situation and the fate of his country on the BBC in London and on September 8, 1939, he started a series of regular radio addresses to the Czechoslovak people.

After the war, Jan Masaryk returned to Czechoslovakia, where he served again as a Foreign Minister. In 1947 Czechoslovakia agreed to participate in the US-funded Marshall plan, a decision unpalatable for the Soviets. In July 1947, Masaryk and the Communist Prime Minister Klement Gottwald went to Moscow to negotiate. "I left as a minister of a sovereign state but have come back as Stalin's lackey," Jan Masaryk said immediately after his return from the Soviet Union.

The events of 1947 gradually led to the Communist takeover in February 1948, when the majority of ministers, Jan Masaryk not included, handed over their resignation to president Benes in the hope that fresh elections would be held. Instead, the president accepted their resignations and a communist government was formed. Two weeks after Jan Masaryk met his end on the ground beneath his bathroom window. His death remained unexplained until today, despite the following series of investigations in 1948, 1968-69, 1993-96.