The support from the FDGB ended when Herbert Warnke was replaced by Harry Tisch as the chairman of the FDGB in 1975. Tisch had begun his political career in Rostock and instead gave his support to F.C. Hansa Rostock. This event was remarkable, as it revealed the large influence that high-ranking politicians exerted on football in East Germany. 1. FC Union Berlin would then had to rely on support from the regional district administration of the ruling SED party in East Berlin and local state-owned enterprises. The main sponsors would be VEB Kabelwerk Oberspree (KWO), VEB Transformatorenwerk Oberschöneweide (TRO) and VEB Werk für Fernsehelektronik (WF). 1. FC Union Berlin developed a bitter rivalry with BFC Dynamo, which was supported by the Stasi. While their arch rivals won 10 titles in a row, Union yo-yoed between the DDR-Oberliga and the DDR-Liga with very little success. Union managed to win the East German Cup in 1968 when they defeated FC Carl Zeiss Jena 2–1 although they lost in their second cup appearance in 1986 to 1. FC Lokomotive Leipzig by a score of 1–5.