DACIA. - Under this name in the imperial age was included a vast region of central Europe between Sarmatia and Germany, which was roughly bounded on the west by the Tisia (Theiss), on the south and south-east by the Danube, touching toward the east the lower course of the Tyras (Dniester) and the Carpathians.
The corresponding modern regions would be Transylvania, Wallachia, Moldavia. The Dacian inhabitants (Dai, Getae) were akin by stock and by language to the Thracians. Toward the end of the Roman republic their king Burebista united many of their tribes into a single state, which aroused concern on account of his enterprise, to such an extent that Julius Caesar, proconsul of Cisalpine Gaul and of Illyricum, seemed destined to turn his arms against him instead of toward the conquest of Transalpine Gaul. The danger to the Roman frontiers was renewed a century later, when once again an energetic sovereign, Decebalus, kept the Dacian tribes united.
During the empire of Domitian there was repeated fighting against the Dacians and not always with good success, so that Trajan had to undertake two very arduous expeditions which led to the complete subjugation of the country (in 1073).
Reduced to a Roman province, and provided with roads, military camps, and colonies, it did not however have very secure frontiers, to such an extent that, as the barbarian pressure became ever more serious throughout the 3rd century, the emperor Aurelian in 271 resolved to bring back to the south of the Danube the occupation troops and colonists, giving as a commitment and as a remembrance to a part of the province of Moesia the name of D., which was then divided into D. Ripensis on the river and D. Mediterranea around Sardica (Sofia). Within the frontiers of what was the province of D., between 107 and 271, soldiers and colonists introduced various religions and cults, and the epigraphic texts with dedications to various Greco-Roman, Syrian, and Persian (Mithras) divinities are relatively abundant. Christianity must therefore also have penetrated there, but the traces of it are scanty, much less abundant, for example, than in neighboring Lesser Scythia, on the coasts of the Black Sea, south-east of the Danube. Mention is made of some sepulchral inscriptions at Napoca (Cluj, Koloszvar), at Sardica, a sarcophagus in the museum of Belgrade, crosses in relief near Drobeta, a Christian lamp at Luciu, a Constantinian monogram on gold bars found at Czofalva in Transylvania (CIL, III, 8080). Even if one were to admit, as St. Jerome wishes (Epist., 59), a preaching of St. Paul as far as Illyricum, and were to accept the claims of the Church of Sirmium (Mitrovitza) to go back to apostolic times, all this would not concern D., which the Danube separates from Illyricum.
The new D. of Aurelian, the one south of the Danube, had bishoprics in the 4th century, among them the flourishing one of Sardica, where a council assembled in 343, and that of Renesiana, made illustrious by the work of the bishop St. Nicetas (cf. the carmen de Niceta of St. Paulinus of Nola: the Saint speaks of D. Mediterranea and of the Ripensis, and calls the Dacians of the other bank Getae).
In the time of Justinian a bishop of Aquae in D. Ripensis is known, from whose jurisdiction places on the left bank of the Danube also depended.
Bibliography2 works
Roberto Parbeni