Antonio Tocco was the third son of Leonardo V Tocco, titular Despot of Epirus and Count Palatine of Cephalonia and Zakynthos, and the eldest to reach adulthood, thus being the heir to his father's titular claims to lands in Greece, and to the fiefs his family had acquired in Italy since the loss of their Greek lands; Refrancore, Apice and Tinchiano.
[4] Given that Leonardo V Tocco had not written a will by the time of his death on 24 January 1641, Antonio's rights as his heir had to be confirmed by the Gran Corte della Vicaria [it], the greatest court in the Kingdom of Naples.
[1] On 4 November 1642, Antonio was granted through diploma the title Prince of Achaea, within the Neapolitan nobility, by Philip IV of Spain.
[5] Antonio did not have a legitimate claim to the original sovereign princely title,[6] however the Tocco were heirs of Thomas Palaiologos (1409–1465) in the female line, twice broken, and therefore descendants of Catherine Zaccaria.
From 1674 onwards, Antonio added 'Prince of Montemiletto, Count of Monteaperti and Baron of Grumo, Montefalcione, Serra and Manocalzati' to his titles.