In Dacia conquered and made a Roman province by the emperor Trajan 105106 and later abandoned by Aurelian 271 275 and N of the lower Danube generally in what is now Romania, the spread of Christianity was due above all to the permanent contacts between the local Daco-Roman population on both banks of the river, conscious of their common origin. An important part was played in the persistence of these contacts and in the propagation and preservation of the Christian religion in present-day Romania by the uninterrupted possession of certain bridgeheads on the left bank of the Danube after Aurelian’s withdrawal, and esp. by the expansion of the Roman Empire N of the Danube, first under Constantine and his successors, and later under Justinian 527565.
A series of small, typically Christian objects found in Dacia Traiana constitute important proof of the spread of Christianity in this area before the Edict of Milan 313, and perhaps even prior to the abandonment of the N Danubian province by Aurelian. Among these objects is the Potaissa Turda, in Transylvania gem intaglio, whose four symbolic representations the inscription ICQUS, the figure of the Good Shepherd symbols of Christ, Jonah symbol of the resurrection and the arbor evangelica symbol of the divine kingdom make it one of the most important finds of early Christian minor art: symbolic in character, it may date from the period of the persecutions.
To the same period are assigned a gem depicting the Good Shepherd, found in Transylvania, and two other gems found in Dacia Inferior at Romula, one with two upright fish with a cross between them, the other with two peacocks supporting a cross with their beaks. The gnostic gems discovered in Dacia Traiana constitute a special category: two at Porolissum Moigrad, Transylvania, three with the inscription Abrasax at Romula and at Orlea district of Olt, and a gold disk with the epigraph Iao Adonai, found at Dierna Orsova. These attest the presence of a significant number of Christian heretics, whether soldiers, merchants or small government employees, who arrived in Roman Dacia from the East Syria or Egypt from the 2nd to the early 4th c.
The large-scale spread of Christianity took place in Dacia Traiana at the time of Constantine and his successors. Left sole emperor 324, Constantine began an offensive policy in the Lower Danube, rebuilding fortresses on both sides of the river, adding new ones and building the bridge between Oescus and Sucidava 328. He also repaired the Roman road running N of Sucidava and re-annexed to the empire the plain between the river and the Carpathians. The most numerous Christian remains of Dacia Traiana have been found at Sucidava Celei – Corabia, district of Olt.
An important find N of the Carpathians in Transylvania once Dacia Superior was the Biertan district of Sibiu donarium, consisting of two bronze pieces: a tabella ansata with the perforated epigraph Ego Zenovius votum posui, and a Constantinian monogram of Christ chi-rho inscribed in a circle; the objects were found with two bronze vases used for worship. A ceramic with monogram and an epigraph similar to that of Biertan were recently found at Porolissum Moigrad, Transylvania; 4th c.. Also probably used in worship was a small bronze lamp ornamented with a cross and a dove found near the city of Dej Transylvania; 4th-5th c.. Christian objects from the same period from Transylvania include a clay lamp found at Apulum Alba Iulia, thought to be of Italian origin, and two local lamps of the same material, one at Ulpia Traiana Sarmizegetuza and the other at Apulum.
Two older Roman monuments, Christianized with the sign of the cross, have been found at ClujNapoca and Ampelum Zlatna. After the great Hun invasion 376453, the last Eastern emperor to consider reconquering Dacia was Justinian. To this end he rebuilt the old bridgeheads on the left bank of the Danube, and together with the military offensive he began another, religious, one, founding the archD bishopric of Iustiniana Prima, which included territory N of the Danube. To this period belong the Christian basilica found at Sucidava and various objects found S and E of the Carpathians: terracotta lamps at Drobeta Turnu Severin, a beautiful bronze lamp at Luciu district of Ialomita, molds for small crosses found at Olteni district of Ilfov, Straulesti Bucharest, Cindesti district of Buzau and Botosana district of Suceava. This material shows the continuity of links between the DacoRoman population and the Roman world later Byzantine S of the Danube.