The spread of Christianity: 2nd-4th centuries

By the end of the 1st century, Christian communities were already established in Rome, the Empire’s capital, and also in the eastern provinces of Asia Minor and Syria.

Over the next three centuries, Christianity spread throughout the Roman Empire, mainly in urban areas. Three cities played a major role in the success of the new religion: Rome, Alexandria and Carthage.

-In North Africa, it is not known when the first communities were established. The first references to their presence in Carthage date back to 180 AD, when a number of Christians were sentenced to death.

In 256 AD, a Council in Carthage brought together 87 bishops, a strong indication of the dynamism of Christianity in this region.

-On the Iberian Peninsula, the first Christian communities were probably set up in cities in the south, but Christianity probably did not spread beyond this area until the second half of the 3rd century.

-In Gaul, the largest Christian community was founded in Lyon, where Irenaeus was bishop.

During the 3rd century, Christianity spread mainly along the valleys of the Rhone, Seine and Rhine Rivers. Nevertheless, Christianity remained a minority religion in Gaul, particularly in the countryside.

There is evidence of Christians in the British Isles, in what is now Great Britain, from around 250 AD, but their numbers were very limited.

In 380 AD, the Edict of Thessalonica, which made Christianity the official – and only legal – religion, confirmed that the Church was widely present throughout the Empire.

Nevertheless, the absence of accurate records makes it difficult to know precisely how many people were Christians at the end of the 4th century, and paganism was still present in the Empire, particularly in rural areas.

During the first centuries, peripheral Christian groups were established outside the Empire’s frontiers.

-The oldest and largest communities were established in Persia.

- Christian communities also existed in Kuwait and Qatar after 225 AD, the Indus Valley from around 296, and Socotra and Kerala shortly after 300.

After 330, the Ethiopian Empire of Aksum was converted by missionaries from Egypt.

-Around 314 AD, Armenia was the first State to declare itself officially Christian, following the conversion of Tiridates the Great.

-In the area around the Danube, the Aryan form of Christianity spread among the Visigoth tribes. The first conversions took place around the middle of the 4th century.  Their numbers grew massively towards the end of the century after the Visigoths settled in the Empire.