Hartmut Bagger was born in Braunsberg, East Prussia (today Braniewo, Poland) and fled the advancing Red Army at the end of World War II to Celle.

He completed a course at the Armed Forces Staff College, Norfolk, Virginia.

From April 1980 till September 1982 Bagger, now an Oberst, was the Chief of staff of the 3.

Bagger was promoted a Brigadegeneral in 1988 and served as the Chief of Staff at the III.

After general Klaus Naumann became Chairman of the NATO Military Committee Bagger followed him as the Chief of Staff of the Bundeswehr on 8 February 1996, a post he held till his retirement on 31 March 1999.