A forged 8th-century document purporting to
record the Roman emperor Constantine's
surrender of temporal sovereignty in W Europe
to Pope Sylvester I (314-25). In the Middle
Ages, this document was used as papal
propaganda in the struggle between pope and
emperor, which was at its most heated during
the Investiture Contest. It was finally
exposed as forged by Nicholas of Cusa and
Lorenzo Valla in the 15th century.