This unique piece where Peter appears in Rome only after other Christian bishops (notice plural!) is known since 1896 but became properly published only as a result of cooperation between Enrica Follieri (1956) and Mario Capaldo (2002). Already Follieri attributed it to South Syrian monasticism and supposed that it was written in an Oriental language. The present Greek and Slavonic recensions go back to a lost Greek archetype being far remoted from it and each other. My analysis resulted in the following. Sitz im Leben: Syrian monasticism of Hauran and Lebanon, second half of the seventh century (Umayyad Caliphate), the time of active Syrian presence in Italia and Rome (when even five Popes were Syrians). Original language: Syriac (one of its hallmarks is Peter’s age of about 160 years, which contradicts to the internal chronology of the account: a confusion in Serto between qof “100” and waw “and”). Original liturgical calendar: a liturgical cycle with Peter’s commemoration on the second Pentecost (as in some Syrian traditions, not on June 29), the whole plot developing within 50 days starting on the first Pentecost. The lost indications of duration for some time intervals are to be recovered as the normal time required for travel (maritime route from Lebanon to Rhegium: 20 days; maritime route from Rhegium to Puteoli: 3.5 ≈ 4 days; from Puteoli to Rome on foot, 200 km: 10 days). The topography of Rome is exact; are mentioned: the ruins of the Temple of Jupiter Capitolinus, piscina in Capitolio, Colosseum, the Old St Peter’s basilica. Target audience: monastic “metropolia” in the East. Message: success in Syrian “colonisation” of Rome.