Augusti in the context of "Tetrarchy"

The pontifex maximus (Latin for 'supreme pontiff') was the chief high priest of the College of Pontiffs (Collegium Pontificum) in ancient Rome. This was the most important position in the ancient Roman religion, open only to patricians until 254 BC, when a plebeian first held this position. Although in fact the most powerful office in the Roman priesthood, the pontifex maximus was officially ranked fifth in the ranking of the highest Roman priests (Ordo Sacerdotum), behind the Rex Sacrorum and the flamines maiores (Flamen Dialis, Flamen Martialis, Flamen Quirinalis).

A distinctly religious office under the early Roman Republic, it gradually became politicized until, beginning with Augustus, it was subsumed into the position of emperor in the Roman imperial period. Subsequent emperors were styled pontifex maximus well into Late Antiquity, including Gratian (r. 367–383), but during Gratian's reign the phrase was replaced in imperial titulature with the Latin phrase: pontifex inclytus ("honourable pontiff"), an example followed by Gratian's junior co-emperor Theodosius the Great and which was used by emperors thereafter including the co-augusti Valentinian III (r. 425–455), Marcian (r. 450–457) and the augustus Anastasius Dicorus (r. 491–518). The first to adopt the inclytus alternative to maximus may have been the rebel augustus Magnus Maximus (r. 383–388).

The Severan Tondo or Berlin Tondo from c. 200 AD is one of the few preserved examples of panel painting from classical antiquity, depicting the first two generations of the imperial Severan dynasty, whose members ruled the Roman Empire in the late 2nd and early 3rd centuries. It depicts the Roman emperor Septimius Severus (r. 193–211) with his wife, the augusta Julia Domna, and their two sons and co-augusti Caracalla (r. 198–217) and Geta (r. 209–211). The face of one of the two brothers has been deliberately erased, very likely as part of damnatio memoriae.

On the viewer's right is Septimius Severus, and to the left Julia Domna. In front of them are the boys Caracalla and Geta. All wear jeweled gold wreaths and imperial insignia, some details of which have been lost. The dating of the piece has caused some debate among scholars, with the final consensus being c. 200 AD. The tondo has many stylistic connections to Fayum Mummy portraiture including materials and artistic elements, and its production has been located in the Fayum district of Egypt during this period. Later on the tondo re-emerged from the antiquities trade; the provenance is unknown before entering the Antikensammlung Berlin (inventory number 31329) in the 20th century. It is now in the Altes Museum.