The shift that occurred in the Roman Empire had to do with the rise of Christianity and its widespread acceptance. When the Roman emperor Constantine issued an edict which tolerated all religions, the split began. With Constantine continuing to practice Christianity heavily he decided to move his headquarters from the west to the east to a capital in Byzantine called Constantinople. Later rulers of the Byzantine Empire would make Christianity the state religion and furthering itself from the romans. The art in this period was devoted to Jesus and all things dealing with Christianity. Many churches were built and each one grand and decorated with mosaics depicting Christ in various forms, much like the interior dome of Santa Maria la Nuava a 12th century byzantine church in Sicily that showed Christ as the Pantokrator.
The middle ages in Europe describe the period of time between the final western Roman emperor and the Renaissance. During these times many styles of art and architecture were born. Animal style which focused on works made up mostly of animal images and intertwined line pattern.an example on this style would be the Lion from the Gospel Book of Durrow created by Irish monks the page features interlocking lines as a border and an intricate lion in the center signaling the beginning of the Gospel of Mark . Also during the early middle ages Carolingian began to form in France. Named for Charlemagne the Frankish emperor at the time, he believed himself to be holy and asked for a chapel to be built in his home. The chapel resembled Roman churches of the past was made for worshiping Christ but was much more substantial than its prototypes. Next in the high Middle Ages came the Romanesque and gothic periods based on old roman architecture. The Romanesque period came first dated 1050 to 1200 the architecture in the period drew from the old southern portion Roman Empire i.e. "overall massiveness, thick stone walls, rounded arches, and barrel vaulted stone ceilings" . While the gothic period 1200-15th century which took a more northern approach, attributed to the Goths of the 4th and 5th century i.e. "stained glass, pointed arches, ribbed vaulting ,and flying buttresses". As seen in the Chartres Cathedral the gothic and Romanesque architecture are both visible because the cathedral was completed at different times. Throughout all these time periods we have been given plenty architecture and art to marvel in from churches and cathedrals to mosaics and tapestry for years to come.