Imperial diptych Imperial diptych In Late Antiquity, an imperial diptych is a theoretical type of ivory diptych, made up of two leaves of five panels each and each with a central panel representing the emperor or empress. They are so-named in contrast to consular diptychs. They were produced as unique examples, whereas each consular diptych was produced in large numbers to offer to the emperor on certain occasions, principally a nobleman's entry to the consulship. No complete example of an imperial diptych survives and so their existence is contested. The ivories specialist R. Delbrück has theorised that the 19 surviving fragments of
Ildefonso Altarpiece Ildefonso Altarpiece The Ildefonso Altarpiece is a triptych painting by Peter Paul Rubens, dating to between 1630 and 1631. It is now in the Kunsthistorisches Museum of Vienna. It is named after the central panel, which shows Saint Ildefonsus's vision of the Virgin Mary, in which she gave him a "casula". On the side panels are Isabella Clara Eugenia and Albert VII, regents of the Spanish Netherlands, with their patron saints Albert and Elisabeth of Hungary. Albert had founded the Ildefonso Brotherhood in the church of Saint Jacques-sur-Coudenberg in Brussels, to encourage loyalty to the Habsburg dynasty - the altarpiece