The primitive history of the church of Catania records at the time of the persecution of Decio in the 251 the martyrdom of the virgin Agata; and in the first years of the IV century (303-304), in the persecution of Diocleziano, that of Euplio, popular form for Eupoli.
The Passio s. Agathae is not anterior to the V century and is a pious reading rather than a historical testimony; while the "Acta Eupli" though rehandled and interpolated they certainly have their base in a genuine and contemporary editing of which they preserve two fragments of questioning . The two martyrs are marked in the geronimian martyrology and in the costantinopolitan "sinassarium" under various dates; but their historicity and chronology are unquestionably based on the epigraph of Julia Florentina, the pagan converted, "fidelis facta", that was buried "pro foribus martyrorum". The fame of Agatha becomes soon vast; the Sicilian virgin is recorded in the carthaginian calendar , authoritative document of the V century. Already in this period churches in his honor are erected in Rome. The archeological documents of the first catanian Christianity are necropolises of pits sub divo, in the impossibility to obtain real catacombs from the hard wash. Lost partly, probably for new volcanic castings and earthquakes, they are confused with the necropolises of Roman imperial age, or in these they represent groups and accessions. In the actual Viale Regina Margherita toward s. Maria of Jesus and the hill of Cibali, in the Oriental pull of Corso Vittorio Emanuele between Piazza Cathedral and the sea, and from Via Sangiuliano (already Lincoln) to Piazza Bellini (already Porta Aci), from the actual Piazza Stesicoro until beside the church of the Carmine, they are been bare, in good number, "formae" that the material and epigraphic data declare like clearly Christians; on the subject, that funeral enclosure in which they had recognized a sepulchral area of family, or good, of Christian community is very important; it is in Via Consoli and it belongs to the first of these cemeteries, with Christian epigraphs, Greek frets and Latin. Between the titles of these necropolis they are counted some of the most interesting documents of the primitive Christianity, dated and between the most ancient of all Sicily. We have already pointed to the most ancient one, that brings, as date of birth of the dead person, the chronological reference of the year in which a Capitolino was the second consul, that is the year 274; therefore the epigraph has to be brought between the end of the III century and the first decades of the IV century, probably the 296. A second one with the consulate of Amazio and of Albio is of the year 345. The most famous of all, that of Julia Florentina, dates back to the times that certainly preceded the peace of Costantino, probably still to the time of the persecutions.In the complex Catania occupyed the site of the preceding inhabited area; everyone knows, in fact, as the external layout of the city is conservative for all the antiquity, even if in their inside the density of the buildings could change. Those walls that must be admitted- being the expression of Procopio that Catania has not strengthened to understand in a general sense, in other words like deprived of garrison- and of which is a sign the mention of a Door of the Ariani in the actions of s. Leo the Taumaturgo, they had to follow substantially the ancient classical surrounded, with any not big variation.