How did basilicas expand under the rule of Constantine?

Answer 1

AnswerBefore Constantine, there were already many impressive Christian churches in the Roman Empire, although many of them were destroyed during the Great Persecution of 303-311 CE, while others had been closed. Constantine had these churches returned to Christian ownership and fully restored.

The basilica style of church was an innovation undertaken by Emperor Constantine, who wished to have magnificant churches built throughout the empire. They were built at state expense, sometimes on the sites of expropriated pagan temples and using treasures plundered from the temples.

So great was the building program undertaken by Constantine, that proper design and construction methods were not enforced, and appropriate materials were often in short supply. Some of the most important new basilicas were already in need of urgent repair at the end of his reign.