Deaths on June 20

Kurt Alder, German chemist and academic, Nobel Prize laureate (b. 1902)

Kurt Alder (German pronunciation: [ˈkʊʁt ˈaldɐ] (listen); 10 July 1902 – 20 June 1958) was a German chemist and Nobel laureate.

13 May

Richard Nixon
During a visit to Caracas, Venezuela, Vice President Richard Nixon's car is attacked by anti-American demonstrators.
30 May

Arlington National Cemetery
Memorial Day: The remains of two unidentified American servicemen, killed in action during World War II and the Korean War respectively, are buried at the Tomb of the Unknown Soldier in Arlington National Cemetery.
16 Jun

Hungarian Revolution of 1956
Imre Nagy, Pál Maléter and other leaders of the 1956 Hungarian Uprising are executed.
18 Aug

Lolita
Vladimir Nabokov's controversial novel Lolita is published in the United States.
28 Nov

French colonial empire
Chad, the Republic of the Congo, and Gabon become autonomous republics within the French Community.