Hans-Dietrich Genscher

Hans-Dietrich Genscher, West Germany’s long-serving foreign minister, visits President Reagan in the Oval Office in 1988.

(Doug Mills / Associated Press )

April 2, 2016 6:52 PM PT

Genscher during a 1989 White House visit with President Bush.

(Barry Thumma / Associated Press )

German Chancellor Angela Merkel congratulates Genscher at a celebration of his 80th birthday in 2007.

(Johannes Eisele / AFP/Getty Images)