Hans-Dietrich Genscher (21 March 1927 – 31 March 2016) was a German statesman and a member of the liberal Free Democratic Party (FDP), who served as Federal Minister of the Interior from 1969 to 1974, and as Federal Minister for Foreign Affairs and Vice Chancellor of Germany from 1974 to 1992 (except for a two-week break in 1982, after the FDP had left the Third Schmidt cabinet), making him the longest-serving occupant of either post and the only person to have held one of these positions under two different Chancellors of the Federal Republic of Germany. In 1991 he was chairman of the Organization for Security and Co-operation in Europe (OSCE).

A proponent of Realpolitik, Genscher has been called "a master of diplomacy". He is widely regarded as having been a principal "architect of German reunification". In 1991, he played a pivotal role in international diplomacy surrounding the breakup of Yugoslavia by successfully pushing for international recognition of Croatia, Slovenia and other republics declaring independence, in an effort to halt "a trend towards a Greater Serbia". After leaving office, he worked as a lawyer and international consultant. He was President of the German Council on Foreign Relations and was involved with several international organisations, and with former Czech President Václav Havel, he called for a Cold War museum to be built in Berlin.