The long period of the Middle Ages is inscribed between two particularly important dates: 476 A.D., which coincides with the deposition of the last Western Roman emperor - Romulus Augustus - and 1492, the year of the discovery of America. The earliest considerations of this historical period are rooted in and take off from the Renaissance.

From the 15^th century onward, any negative reference to the Middle Ages was emphasized more and more, highlighting the barbaric aspects perpetrated during the previous centuries and thus justifying the name of "The Dark Ages" attributed to it. However, it was not until 1688 that, through the figure of Christoff Helter, the Middle Ages was institutionalized as a historical period.

But when was the Middle Ages actually born? Is there a work that encapsulates the origin of this new era?

The monument we can certainly take as an example is the Arch of Constantine in Rome, a stone's throw from the Colosseum and thus in the heart of the empire. The Arch was commissioned (paid for and desired) primarily by Roman senators to celebrate Constantine's victory over his enemy Maxentius and was built in 315 AD. The structure echoes the usual structure of three-arched arches found since ancient times, such as the Arch of Septimius Severus still found in the Roman Forums. The peculiarity of this new architectural structure, unlike the previous models made, is the reuse of already existing material and therefore not made ad hoc for the Arch of Constantine.

In the Middle Ages, in fact, is particularly common the use of so-called "perusal," which carries with it two distinct meanings. The first is of encomiastic origin in regard to the previous grandiose emperors who are considered as examples to be emulated, going on to reuse materials used for their celebratory monuments. The second is of economic origin, because it allows the use of material already present in the city of Rome - considered during the Middle Ages as a veritable open-air quarry - without the need to purchase it in some distant eastern location. In this case, sculptural elements from the time of Trajan, Hadrian and Marcus Aurelius were reused. In contrast, two bas-reliefs representing the Oratio and Liberalitas, or respectively the emperor's inaugural speech and the bestowal of gifts by the emperor, were made specifically for the Arch of Constantine. The stylistic difference between the different periods immediately leaps to the eye.

If, in fact, in the reused perusal elements to emerge is a precise correspondence between subject and object, a perfect mimetic representation of reality, for the fourth-century reliefs it is the paratactic repetition of some segments and two-dimensionality that dominate. Moreover, the focus cannot but fall on the central character of the two bas-reliefs, namely Constantine, the real key element of the context: to make the entire composition lose its meaning, it would be enough to eliminate the pivot around which the whole scene is built. On the contrary, what happens in the bas-reliefs of the late antique period, what is represented is a cross-section of the society of the time, an everyday scene, which develops independently of the figure of the emperor present.

This is a substantial difference that will be the basis of the art-historical change that will initiate the new era of the Middle Ages. But was this substantial formal difference specifically intended for the Arch of Constantine? The answer is affirmative. The Arch of Constantine stands as the political manifesto of fourth-century Rome, demonstrating the total dependence of the Empire on the figure of its emperor Constantine, emphasizing all his auctoritas.