The sculptural group has been fixed to a corner of the façade of St Mark's Basilica in Venice, Italy since the Middle Ages.

Spolia from the Fourth Crusade, the statues were originally designed as two separate sculptures, each consisting of a pair of armoured late Roman emperors embracing one another.

The system finally ceased to exist around 313,[2] and though this form of government was short-lived, it served to separate military and civic leadership roles and was one of the first examples of balanced power.

This latter theme seems to be reflected by the fact that all four tetrarchs are armed, wearing military garb, an unmistakable representation of collective power.

The tetrarchy gave way to a united Roman Empire in the time of Constantine, as the emperor took control over the east and west halves in 324.

[5] When Constantine refounded Byzantium as "New Rome" - Constantinople - in 328–330, he relocated numerous historically or artistically significant monuments and sculptures to the city.

Comparing them to the slightly later reliefs on the Arch of Constantine in Rome, Ernst Kitzinger finds the same "stubby proportions, angular movements, an ordering of parts through symmetry and repetition and a rendering of features and drapery folds through incisions rather than modelling".

Noting other examples, he continues "The hallmark of the style wherever it appears consists of an emphatic hardness, heaviness and angularity — in short, an almost complete rejection of the classical tradition".

[8] On the contrary, another theory considers the classical style sublimated in a formal stream that manages to unite three different cultural elements: Greek-Roman, Barbarian-Celtic and Persian-Sasanian, which would make the monument not only a symbol of timelessness and profound mysticism of power, but also a visual and cultural glue between East and West, in a framework of ideal solidification of the universal empire of Rome.

The comparative vividness of porphyry to other stones underscored that these figures were not regular citizens, but many levels above, even reaching to the status of gods, and worthy of the respect they expected.

[18] This was commonly practised to suggest their likeness to them in character and their legitimacy to rule; in short, these fictitious additions were meant to persuade their subjects that they would be as great and powerful a leader as the previous ruler had been.