Constantine the Great initiated major changes when he recognized Christianity as the official Roman religion in the 4th century AD. This included moving away from the naturalistic classical style toward a more symbolic style. Figures under Constantine lost individuality and detail, appearing militaristic with crude carving. In contrast, art from the reign of Augustus in the 1st century AD featured natural poses, spatial depth, and shading to depict volume. Mosaics from the Byzantine period after Constantine further developed this symbolic style with gold backgrounds, frontal figures lacking weight, and emphasis on hierarchy and symmetry rather than naturalism.