It was natural for Christianity to spread more slowly in the internal and peripheral zones of the Roman Empire, especially in the absence of cities and where the countryside was dotted with small villages or just isolated houses. Moreover, whereas in Rome the preaching of St. Peter attracted more and more followers, farther away the strongly rooted cult of the gods of Rome persisted, often associated with magical elements having to do with agricultural activities. Earlier, in Republican Rome, veterans retiring from the army were given land to cultivate, far from the City, and this practice continued in the imperial period. In Etruria, alongside names of Etruscan farmers and shepherds, placenames such as fundus certinianus or fundus persinianus appeared, farms identified by their proprietor’s name. In addition to retired centurions and legionaries, rich Roman citizens also established villas and agricultural properties (such as villa laetoriana, today called Traiana). Evidence of this near Gropina is the clay and ceramic material found along the Cassia Vetus, today the Setteponti road, the same road by which early Christianity, that of St. Peter and of the catacombs, was to reach the land of the Etruscans.
This land was dotted with small groups of rural houses, or
vici (a single one called a vicus paganus, or rusticus), also grouped together in pagi, larger territorial areas (from pagus the term “pagan” was derived, which only later would come to mean “non-Christian”).
The lands cultivated by the Romans maintained the characteristic land divisions established in the Republican period by Lucio Cornelio Silla or, according to others, by the Gracchi, and still recognizable today in the valley below the area of Gropina. This helps to explain the strong “resistance” of the ancient gods in this area, as in other peripheral zones of the empire. Nevertheless, little by little, a growing number of followers of the new religion began to travel along the Cassia Vetus, bumpier but safer than the Adrianea (which was often subject to inondations as well as the transit of troups), making pilgrimages to visit the tomb of St. Peter in Rome: in the opposite direction Christianity travelled up this
via Sancti Petri and spread into the small communities, and also to the villas and large estates, without distinction of social class.
At first, Rome did not give much importance to the Christians, seeing them as a meager number of representatives of one of the many religious sects that presented no threat to the stability of the empire. Only later, as Christians were becoming exponentially more numerous, were a few emperors to think it opportune to fight them, also for political reasons: Christians who refused to sacrifice to the gods who assured Rome their protection, would be accused of subversion and crimes against the state. The spread of Christianity among Roman soldiers was remarkable: many of them were worshippers of Mithra, a divinity of Persian origin, a benevolent god whose birth as
Sol Invictus was celebrated on December 25 from the time of the emperors Heliogabalus and Septimius Severus (3rd century A.D.). In certain ways the figure and the story of Mithra, and especially the fundamental concept of Mithraism, the struggle of good against evil, share general analogies with the story of the Christian messiah, and this helps to explain the spread of the new religion among the soldiers. Many Christian churches were to be built over Mithraic or other pagan temples: an evident, tangible, “superimposition,” aimed at discouraging the pagan cults, which was to culminate also in the decision to celebrate the birth of Jesus on December 25, the day of the birth of the Sol Invictus: Jesus Christ as the new and only Sun of the world. Pagan themes invested with Christian meanings were also to appear in the pieve of Gropina.
After the earliest centuries of the empire, following Costantine’s edict of 313, the new religion had reached the areas farthest from Rome, including the Valdarno. The first churches are built, called
chiese in Italian from ecclesiae, which means assemblies of the faithful, and in time, all along the Cassia Vetus the pievi of Cascia, Piandiscò, Gropina, and San Giustino were built: the word derives from plebs, people, and designates a church with a baptismal font. And Gropina was to have its first church very early, already by the 5th-6th century.