Guetersloh, Germany  - Reinhard Mohn, who converted a minor German printer of prayer books into one of the world's greatest media conglomerates, has died at the age of 88, the Bertelsmann Group said Sunday.

Mohn took charge of C. Bertelsmann Verlag in 1947 and was its chief executive until 1981. Over the years, the Bertelsmann group expanded into book clubs, general book publishing, magazines and television, setting up subsidiaries in many nations.

The company said he died on Saturday.

He and his wife, Liz Mohn, led the fifth generation of the Bertelsmann and Mohn clan, which still retains control of the business and associated charitable foundations. Before he took over, the business had mainly focussed on publishing religious books.

Today, Bertelsmann's Random House unit is the world's principal general books publisher. Bertelsmann operates huge printing works and was once a major force in recorded music, before ceding to Sony the control over their joint venture.

Bertelsmann Stiftung chairman Gunter Thielen said Mohn had been one of the outstanding personalities of Germany's economic and social recovery from the Second World War.

Mohn was born June 29, 1921 in the small northern German city of Guetersloh where Bertelsmann still has its head office.

After war service in which he was taken prisoner, he completed a training in bookselling and took over the family firm. In 1977 he set up the Bertelsmann Stiftung, a foundation to hold the stock, and transferred majority control of the companies to it in 1993.

Currently, Bertelsmann Stiftung, which does extensive public education and other charity work, holds 76.9 per cent of the group.  dpa