The Byzantine empire was renowned for its mosaics. And many of these incredible works of art celebrated the union of church and state. The spread of Byzantine mosaic culture was not restricted to Constantinople, but spread to distant regions of the empire, including the Balkans, southern Italy, and parts of Russia.
In fact, the rapid increase in mosaic artists who possessed the technical mastery and aesthetic sense of this artform led to huge cross-cultural influences, including Islamic art styles, especially by the Abassids and the Umayyads. While the messaging was politico-religious, it was impossible to ignore the distinctions in style and aesthetics, and the resultant beauty.