Gelberg was born in
Dortmund and later lived in
Weinheim,
Baden Württemberg. Gelberg founded in 1971 the children’s book series Beltz & Gelberg as part of the publisher . The initial eight books grew to 1000 titles in 25 years. He published a magazine for youth literature,
Der bunte Hund, around three times per year. He began a yearbook for children's literature in 1971, which appeared until 1999. Since 1982, Gelberg collaborated with ,
Janosch and
Peter Härtling for individual issues of the magazine. Gelbert published work by writers for children including , , ,
Erwin Moser,
Christine Nöstlinger,
Rafik Schami and . He lectured at the
University of Frankfurt. In 2011, he published an anthology of poetry for children, entitled
Wo kommen die Worte her? (Where do the words come from?). It contains poems by more than 100 authors expressly written for the book, and also older poems by
Christian Morgenstern and
Joachim Ringelnatz, among others. Gelberg died on 17 May 2020 in a hospice in Weinheim, aged 89. == Awards ==