Queen Elizabeth II shakes hands with Martin McGuinness, the deputy first minister of Northern Ireland, as First Minister Peter Robinson, center, looks on at the Lyric Theatre June 27, 2012 in Belfast, Northern Ireland. McGuinness, a former Irish Republican Army commander, was the outlawed group's chief of staff when it assassinated Lord Louis Mountbatten, the queen's cousin, in 1979.
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U.S. President Clinton watches as Israeli Prime Minister Yitzhak Rabin shakes hands with Palestinian leader Yasser Arafat in the garden of the White House after the signing of the deal transferring much of the West Bank to Palestinian control Sept. 13, 1993. The agreement, which did not pan out, also called for a final settlement between the two groups by February 1999.
South Africa's President F.W. de Klerk, left, and African National Congress President Nelson Mandela shake hands in goodwill May 4, 1990 at a joint news briefing, after historic "talks about talks" between the South African government and the ANC in Cape Town on ending white-minority rule.
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U.S. President Reagan and Soviet leader Mikhail Gorbachev, right, meet for the first time before summit talks at the villa Fleur D'Eau at Versoix near Geneva, in this Nov. 19, 1985, file photo. The pair's handshake came to symbolize the start of a thaw in the frosty relations between the two Cold War superpowers.
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Egyptian President Anwar Sadat, standing, shakes hands with Israeli Prime Minister Menachem Begin in the Israeli Parliament, Nov. 20, 1977, after Sadat addresses the Knesset. Sixteen months later, the two nations signed a peace treaty.
Chinese Communist leader Chairman Mao Zedong, left, welcomes U.S. President Nixon at his house in Beijing Feb. 22, 1972. This historic visit marked an end to 25 years of division between the two governments.
Winston Churchill, Harry Truman and Josef Stalin seal an agreement established during the Potsdam conference concerning the fate of Germany with a symbolic handshake in July 1943. The Allied leaders met to discuss Europe after the fall of the Nazis and warn Japan to give up its fight in the Pacific.
After this handshake Sept. 23, 1938, British Prime Minister Neville Chamberlain and Germany's Adolf Hitler agreed that in exchange for tolerance of German occupation of the Sudetenland, Hitler would bring "peace in our time." This promise was broken and so began World War II.
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On April 9, 1985, General Robert E. Lee of the Confederacy surrendered to General Ulysses S. Grant at Appomattox Courthouse. The handshake ended the U.S. Civil War.
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