The Byzantine style dates back to the IVth-Vth century period. It develops in three stages during the IVth-VIth, VIth-XIIth and XIIth-XVth centuries.
In the first period, most churches had a basilicas-type base (taken from the old roman basilica), with 3, 4 or 5 naves. As an exception, the San Vitale church of Ravenna had an octagon-inside-a-square base. The most famous characteristic of this style is the type of decorations chosen for the interior: mosaics and icons (High Sofia of Constantinopoles and San Vitale of Ravenna are world famous for their mosaics).
Through its size and space-effect of the interior, High Sofia is a representation of the infinity of the universe that makes us meditate at our size compared to that of the cosmos.
In the same century churches with a Greek-cross ( St. John church of Efes) and octagon-inside-a-square like base begin to be built.
In the IXth century the Greek-cross imposes itself, the cupola is sustained directly by the walls (pylons are no longer used) and external decorations begin to appear: blind arcades, coloured bricks and in the Xvth century, sculptures and wall-paintings.
The third period of the Byzantine style begins in the Xvth century, with the Comneni dynasty. The most important monuments of the period are the Pantokraton church, burial place for ten generations of emperors from the Comneni and Paleologi dynasties, and Chora (today Kahrie Djami), the most elegant Byzantine church after High Sofia.