The Forum of Trajan, which was inaugurated in 112 AD, completed the big monumental district of the Imperial Forums. The Column of Trajan was completed the following year, together with the renovations to the Temple of Venus Genetrix in the Forum of Caesar. In order to create the huge complex (300 x 185 m) space was obtained by cutting into the slopes of the Capitoline and Quirinal Hills, which until then had been connected by a saddle. The excavation works had probably already started under Domitian at the same time as the layout of the Forum of Nerva. The works were interrupted after the death of the emperor, who was murdered in a conspiracy in 96 AD. Continued by Trajan, they were financed with the conquest of Dacia (now Romania). The conquest was conducted in two campaigns (101 -102 and 105 -106 AD) and ended with the defeat and subjugation of the Dacians and the death of their king Decebalus.
The architect of the work was Apollodorus from Damascus, who was the military engineer that had accompanied the emperor in the victorious war. The plan of the Forum of Trajan was more complex than that of those built by his predecessors. In fact, it included a vast square, flanked by porticos with exedras set back into them. On one side was the Basilica Ulpia that is thought to have housed a library, behind which was the Column of Trajan. On the opposite side, the square was closed by a large three sectioned hall (a rectilinear central sector and lateral sectors that faced inward). Its monumental columned façade formed the background for the colossal equestrian statue of the emperor, behind the central sector of which was a quadrangular courtyard that connected the new forum with the Forum of Augustus.
The history of the “Markets” of Trajan started with the planning of certain proprietary works during the construction of the last and greatest of all the imperial forums, that of Trajan. Even if we have clear accounts to classify the Markets of Trajan, ancient records do not offer steadfast evidence on the imperial financers and the conceptual origins of the project. The most plausible explanation is that the great complex was perhaps conceived as a sole unit along with the neighbouring forum. It is highly likely that the complex had already been ordered by Emperor Domitian and taxation stamps, the only direct source available, show an index number consistent with the Domitian era. A theory further sustained by our knowledge of the ambitious building programme envisaged by this emperor. Another premise puts the selling off of a notable quantity of stockpiled bricks and building materials after the emperor’s murder as the main impetus for the construction of the complex. However, archaeological data gathered in recent studies (2003-2007) seem to indicate that preliminary works for an imposing architectural complex had already began under Domitian. Works included terracing walls and sewage piping.
Current knowledge leaves little to support the traditional interpretation of the structure as having a primarily commercial use. Recent archaeological discoveries have been fundamental in contributing to a rereading of the complex. Inscriptions on the structure’s main beams, which were reused as braces in the ground works for the Milizie Gardens, make testament to a procurator fori traiani, one Horatius Rogatus, who would have restored the forum after a fire in the 3rd century AD. The functional differences of the various buildings that make up the Markets of Trajan are evident that the lower section had close association with activities administered by the adjacent forum with the upper section instead being dedicated to activities of a more managerial and administrative nature.
The Basilica Ulpia was an ancient Roman civic building located in the Forum of Trajan. It was named after Roman emperor Trajan whose full name was Marcus Ulpius Traianus. It became perhaps the most important basilica after two ancient ones, the Basilicas Aemilia and Julia. With its construction, much of the political life moved from the Roman Forum to the Forum of Trajan. It remained so until the construction of the Basilica of Maxentius and Constantine. Unlike later Christian basilicas, it had no known religious function; it was dedicated to the administration of justice, commerce and the presence of the emperor. It was the largest in Rome measuring 117 by 55 meters (385 x 182 ft). The Basilica Ulpia was composed of a great central nave with four side aisles with clerestory windows to let light into the space divided by rows of columns and two semicircular apse, one at each of the ends with the entry to the basilica located on the longitudinal side. The columns and the walls were of precious marbles; the 50 meter (164 ft) high roof was covered by gilded bronze tiles.
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