Demetrius' claim to represent Byzantine royalty rested on a claimed connection between the Rhodocanakis family and the ancient Byzantine Doukas family, as well as on one of his supposed ancestors, also named Demetrius Rhodocanakis, having married a daughter of Theodore Paleologus, a possible descendant of the Palaiologos emperors.

In addition to his pretensions, Demetrius is also remembered as a bibliophile and book collector as well as an important figure in the history of freemasonry in Greece.

Nikephoros' revolt supposedly took place in the direct aftermath of the failed usurpation of Constantine Doukas in 913, a real historical event.

[3] Rhodocanakis' claims were collected and published by him in 1870 in London, under the title The Imperial Constantinian Order of Saint George: a review of modern impostures and a sketch of its true history.

Among Theodora's younger children was supposedly Constantine Rhodocanakis (1635–1687), a real historical figure, whom Demetrius later claimed was his relative.

[12] At the time of his forgeries, Demetrius claimed that his father Ioannes (or "Joannes X Ducas Angelus Comnenus Palaeologus Rhodocanakis"), was the titular emperor of the Byzantine Empire.

[17] Demetrius accepted the legendary and invented origin of the order, but not the genealogical claims of the Angelo Flavio Comneno family, and dismissed them as Italian pretenders and impostors, claiming that his lineage, supposedly deriving from the Palaiologos emperors, represented the true line of grand masters.

[14] In his 1870 book, Demetrius had accused the papacy of ruling against his own ancestors in favor of the Angelo Flavio Comneno family,[14] who had been papally recognized as Byzantine descendants in 1545.

[21] In 1895, Émile Legrand [fr], a reputed French hellenist and byzantinologist, accused Demetrius of inventing one of the books he had cited in his 1870 work, Historia Genealogica dell’Antichissima et Augustissima Casa Duca-Angelo-Comnena-Paleologa-Rhodocanakis, supposedly published in 1650 but in reality non-existent.

[2] After his father's death, Demetrius styled himself as "Demetrios II Dukas Angelos Komnenos Palaiologos Rhodokanakis, fifteenth titular emperor of Constantinople".

[22] In addition to being a pretender, Demetrius was also an active freemason and an important figure in the development of freemasonry in Greece.

On 14 September 1871, Demetrius left for Greece, arriving in Athens on 20 October after travelling through France and Italy.

After his election, Demetrius spent some time travelling through Greece, visiting various lodges to smooth out friction and invite delegates to the council.

[22] Demetrius' insistence that his marriage registration should bear his imperial title led to a lengthy legal process with the Court of Appeals of Athens, which on 27 December 1895 at last ruled in his favor.