Walter Momper (born 21 February 1945) is a German politician and former Governing Mayor of Berlin (West Berlin 1989–1990, reunited Berlin 1990–1991). Whilst Governing Mayor, he served as President of the Bundesrat in 1989/90. He attended the opening of the Brandenburg Gate on 22 December 1989, and, on October 3, 1990, became the first mayor of a reunited Berlin.He was born in Sulingen (near Bremen), today Lower Saxony, and is a member of the SPD (Social Democrats).