The Final Act of the Congress of Vienna, signed on 9 June 1815, reorganised Europe after the Napoleonic Wars. It established a framework for international relations that maintained a fragile equilibrium among the Great Powers for nearly a century, setting the precedent for multilateral diplomacy that endures to this day.
Vienna, 1815 1Intercepted and decoded by British cryptanalysts in January 1917, the Zimmermann Telegram proposed a military alliance between Germany and Mexico against the United States. Its publication decisively shifted American public opinion toward entering the Great War.
Berlin — Mexico City, 1917“Politics is the art of the possible, the attainable — the art of the next best.”
1867Charles Maurice de Talleyrand-Périgord served as foreign minister under Napoleon and played a pivotal role at the Congress of Vienna. A master of survival, he navigated five successive regimes and became the archetype of the professional diplomat — calculating, charming, and utterly indispensable.
1754 – 1838The Peace of Westphalia in 1648 established the principle of state sovereignty that forms the bedrock of modern international law.
Osnabrück & Münster, 1648“We the peoples of the United Nations, determined to save succeeding generations from the scourge of war, which twice in our lifetime has brought untold sorrow to mankind, and to reaffirm faith in fundamental human rights, in the dignity and worth of the human person, in the equal rights of men and women and of nations large and small…”
San Francisco, 26 June 1945 2For centuries, European diplomats referred to the Ottoman government as “the Sublime Porte,” a metonym derived from the grand gate of the Topkapı Palace in Constantinople, where foreign ambassadors awaited audience with the Sultan’s ministers.
Constantinople“When Paris sneezes, Europe catches cold.”
c. 1830George F. Kennan’s 8,000-word cable from Moscow in February 1946 outlined the philosophical foundations of Soviet foreign policy and proposed the strategy of containment that would define American diplomacy throughout the Cold War.
Moscow, 22 February 1946 3Signed on 17 September 1978 by Egyptian President Anwar Sadat and Israeli Prime Minister Menachem Begin, brokered by President Jimmy Carter.
Camp David, 1978Following the Napoleonic Wars, the major European powers — Britain, Austria, Prussia, Russia, and later France — established a system of periodic congresses to resolve disputes through negotiation rather than warfare. This Concert of Europe, though imperfect and ultimately fragile, represented the first sustained attempt at collective security through institutionalized diplomacy.
1815 – 1914The second Secretary-General of the United Nations transformed the office from an administrative post into a tool for preventive diplomacy. His concept of “quiet diplomacy” and willingness to personally mediate crises set the standard for international civil servants.
1905 – 1961