So, direct or implied, the passage of the edict paved way to Art and Architecture with Christian themes.
The Latin word Basilica originally referred to a public building in the center of town. The Roman Basilica, which looked like a large roofed hall, was used as a place for transacting business and other legal matters. The hall is divided by columns which made isles and arcade spaces. In these cubicles are the officials and scribes who attend to the transactions. On one or both ends of the hall is a propped up platform called an apse. This is for the seats for the magistrates. Some times, there are even seats for other people to watch the process of the legal activities. These basilicas looked like covered market places (New World Encyclopedia). This was exactly the purpose for the Basilica Porcia in Rome.
After the edict, Christians, who now had a new found freedom, decided to build buildings and structures for their worship. Temples, although serves a similar purpose, does not suite the practices that are to be made. Temples for the pagan gods serves mostly as deposit boxes for treasures and figures of the gods. There is also the fact that worship practices are done outside of the temple under the open sky. Constantine I made use of the architectural concept of early Roman basilicas as a template for the grand place of worship. The new basilicas were shaped as long rectangles two stories high, with ranks of arch-headed windows one above the other. They also had a center nave with one isle at each side and an apse at one end. This apse is now known as the altar. The word Basilica had changed after the edict. It then meant as a place of Christian worship or a large church which was given a ceremonial blessing of the Pope (New World Encyclopedia). An example of this would be the Basilica of Vitale in Italy.
From then on, basilicas are no longer associated with commerce or politics but of spiritual refuge. Although the center of the city still houses the business and political district, the church is always found near. In fifteenth century Europe, the plazas of cities are considered the center and on opposite sides of the plaza are the church and the town hall. This maintains the concept of keeping the basilica at the center of the city.
The edict of 313 has made a great impact in the architecture and usage of basilicas. But, at present day, both basilica formats are recognized; architectural basilicas are referred to the early Roman version where as the pos-edict basilicas are of the ecclesiastical kind.
The Edict of Milan: Constantine Augustus and Licinius Augustus. University of Pennsylvania. Accessed: March 31, 2009. .
Basilica, New World Encyclop