Though his genealogy was never completely finished, Mills took the titles "Despot and Autokrator of the Romans" and "Duke of Morea", though he never achieved any widespread recognition and never seriously attempted to enforce his claims.

[3][1] As part of his pretensions, Mills produced a genealogy linking him back to the Palaiologoi, which according to the British historian Justin Pollard requires "some suspension of disbelief".

[1] Mills also identified John with a figure who appears in the genealogy of the assassin Theodore Paleologus, there contradictingly indicated as the son of Thomas Palaiologos (Manuel's father).

In Mills' genealogy, his ancestors were a younger line of descendants of John,[7] but became the legitimate heirs to the Byzantine Empire after the extinction of Theodore Paleologus' family in the late 17th century.

[1] Styling himself as "His Imperial Majesty Petros I, Despot and Autokrator of the Romans, The Prince Palaeologus",[1][2] and also claiming to be the rightful Grand Master of the Constantinian Order of Saint George, as well as the "Duke of Morea",[2] Mills usually wore a faux military uniform, or sometimes long flowing robes.

After Mills' death, his son Nicholas denounced the idea that their family were of imperial descent, calling his father's claims a "complete and utter sham" and hoped that "the ghost of Prince Palaeologus might now be buried once and for all".

Several newspapers, such as the Isle of Wight County Press, The Daily Telegraph and The Times, printed obituaries of Mills, identifying him as "His Imperial Highness Petros I Palaeologos".