In 1938, Mainz was forced into a merger with Reichsbahn SV Mainz and played as Reichsbahn SV Mainz 05 until the end of World War II.
1938年被迫與「Reichsbahn SV Mainz」合併，以「Reichsbahn SV Mainz 05」的名義繼續比賽直到第二次世界大戰完結。