The Roman Forum retained its importance especially during the Republican period (5th-1st centuries BC), when the valley gradually filled with public buildings whose remains are still preserved. These buildings, which almost always originally had a timber frame and brick facing, were reconstructed on various occasions, in part because they were frequently destroyed by fire or civil strife. It was this unplanned continuity of its buildings over time which gave the Roman Forum its typically disorderly appearance, without a unitary plan. The area's development peaked with the victorious end of the Punic Wars in the 2nd century BC when four basilicas were built: the Porcia, Opimia, Aemilia and Sempronia. Later, first under Julius Caesar and then Augustus and the early emperors (1st c. BC-1st c. AD), the Forum gradually took on a different role, that of monumental centre and place of religious memory, whilst public life moved to the nearby Imperial Forums. As a consequence building activities were interrupted, with one last moment of glory in the late empire with the construction of the honorary columns and equestrian statues. True decline began with the imperial court's move to Ravenna and the edicts of the 4th century AD decreeing the closure of the temples, some of which were turned into churches. This was followed in the 5th century by the Visigoth and Vandal invasions. The abandoned buildings fell into ruin whilst the ground level of the Forum rose to cover what remained. Buried in vegetation and now on the edge of the city the square became pasture, whence the name of "Campo Vaccino" (Cow's field).