Dede was born 1935 in Nordenham-Blexen. His father was a
Lutheran priest. After school Dede studied during the 1950s. Later Dede worked as a newspaper reporter in
Papenburg,
Gütersloh and
Nordenham. Dede wrote several books over local history in northern part of
Lower-Saxony (Butjadingen, Oldenburg, Bremerhaven, Stedingen, Jade, Wesermarsch) and a book about Jesus Jesus – schwul?, Die Kirchen, die Christen und die Liebe (translated "Was Jesus gay?"). Dede lived in
Oldenburg.