Byzantine art developed out of eastern Roman imperial art and reflected Christian religious themes. It utilized styles like mosaics, icons, and illuminated manuscripts. Major artistic periods included the Early Byzantine era featuring works like the Hagia Sophia and mosaics of Justinian and Theodora, the Iconoclastic controversy which banned religious images, and the Middle Byzantine period when icons were restored. Art was used to convey religious messages and assert political power in monumental church buildings and luxurious objects.