Historical Context
The Iveron monastery was founded by Georgian monks on Mount Athos in Greece in the late tenth century, around 980 to 983, and is traditionally associated with John the Iberian and John Tornike. The OCA's account notes that Georgian monks began to settle on Mount Athos in the middle of the tenth century, with the Georgian monastery of Iveron founded there not long after. The monastery is also known for housing the Panagia Portaitissa icon of the Mother of God.
Iveron suffered a martyrdom of monks at the hands of Latins during the period of Western presence on Mount Athos. An OrthodoxWiki timeline of Orthodoxy in Greece places this event at roughly 1259 to 1280, and the OCA records a collective commemoration of the 'Martyrs killed by the Latins at the Iveron Monastery on Mount Athos.' Procopius is most plausibly to be understood within this same historical context, though no source directly attests the circumstances of his death.
Several other named monastic martyrs of Iveron are commemorated together on May 13 in the OCA calendar: John, George, and Gabriel, each likewise carried with the note that no information is available. Procopius is set apart from these by his distinct June 25 feast, which suggests he was an individual monastic martyr remembered separately within the same tradition. His era and century are not securely attested; if he belongs to the Latin-era martyrdom event, a thirteenth-century date would follow, but this is contextual inference rather than direct record.