he creation of autonomous states in the provinces of the Byzantine Empire also had an effect on architecture. For reasons of prestige and as one way of proclaiming their authority, the new local rulers devoted themselves to the construction of impressive and costly buildings.
This extensive building activity resulted in the creation of local schools of architecture such as those of Epiros or Serbia, each of which possessed its own particular characteristics but which continued to be based on the building practices and architectural solutions of the mid-Byzantine tradition.
The older architectural types continued to be used, while on the Greek mainland a new type of church appeared, known as the
At the same time, in the Latin-occupied areas, besides the transverse-vault churches, most prevalent were simple architectural types, such as the single-cell barrel-vaulted churches. These were usually small buildings without particular external decoration, reflecting the limited means of the local community and of the ecclesiastical representatives who saw to their construction.
In the more central areas of the Empire and in the capital itself after its recovery, little building activity is noticeable and this is usually limited to additions to older churches, such as side-chapels,