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On June 12, 1964, South African leader Nelson Mandela was sentenced to life imprisonment for sabotage and conspiracy to overthrow the apartheid government, in the proceedings known as the Rivonia Trial. Mandela was held at Robben Island Prison for 18 of the 27 years he spent imprisoned. From prison, he became the global symbol of resistance to apartheid.

On June 12, 1898, General Emilio Aguinaldo proclaimed the independence of the Philippines from Spanish rule in Cavite — the first Asian leader to proclaim independence from a European colony. However, the Treaty of Paris of that same year ceded the Philippines to the US, which governed it until 1946. June 12 is Philippine Independence Day.

On June 12, 1987, US President Ronald Reagan delivered at Berlin's Brandenburg Gate his famous speech containing the line directed at the Soviet leader: "Mr. Gorbachev, tear down this wall!". The Berlin Wall fell on November 9, 1989. The phrase, which Reagan included in the speech against his advisers' counsel, is considered one of the most memorable moments of the Cold War.