The Orion Publishing Group Limited was founded in 1991. Soon after, Orion began negotiations with Lord Weidenfeld and acquired Weidenfeld & Nicolson as the nucleus of a new, entrepreneurial publishing group. The W&N imprint, founded in 1949, was an established brand name with a consistent history of quality publishing. Since the 1980s, the imprints under the Weidenfeld umbrella included JM Dent and Everyman Paperbacks.

The Orion Paperback Division was successfully launched in 1993 and two more acquisitions were made at the start of that year. Orion bought the assets of Chapman Publishers, a small general publishing house. The second acquisition was a warehousing and distribution centre, Littlehampton Book Services, based in Sussex.

In 1998, a majority of the share capital of the Orion Publishing Group was sold to Hachette Livre, the French publishing arm of the Lagardere Group. In 2003 Hachette Livre became the sole owner of the group.

In December 1998 the group acquired the publishing house Cassell & Co, whose imprints included Victor Gollancz Ltd. In January 2002, with the acquisition of the Octopus Publishing Group by Hachette Livre, the popular illustrated imprints of Cassell & Co were transferred to the Octopus Group. As a result, the Cassell Reference and Cassell Military lists were joined with the Weidenfeld imprints to form a new division under the name of Weidenfeld & Nicolson Ltd.