Roman Forum historical timeline

A drained marsh that ran a republic, outgrew itself before the emperors arrived, and ended with one column for a Byzantine.

Chronology

1. 8th–7th centuries BC — the Regia, the ancient former royal residence, and the Temple of Vesta stand on the southeastern edge, with the complex of the Vestal Virgins around them. Structural impact: the first permanent buildings on the valley floor. What you see today: their footprints, rebuilt after the rise of imperial Rome.
2. End of the 7th century BC — the valley, anciently a marshy area, is drained, and the Forum begins to take its present form, becoming the centre of public life for over a millennium. Structural impact: dry ground where there was marsh. What you see today: the reason anything could be built here at all.
3. Archaic period — shrines to the northwest, the Umbilicus Urbis and the Vulcanal, develop into the Republic's formal Comitium. Structural impact: an assembly area is defined. What you see today: where the Senate, and Republican government itself, began.
4. 179 BC — judicial activity moves to the new Basilica Aemilia, formally Basilica Fulvia, as the archaic Comitium is replaced by the larger adjacent Forum. Turismo Roma dates the civil basilicas, where judicial activity took place, to the 2nd century BC. Structural impact: roofed halls for the courts. What you see today: the long rectangular foundations along the north side.
5. c. 50 BC — some 130 years later, Julius Caesar builds the Basilica Julia and the new Curia Julia, refocusing both the judicial offices and the Senate itself. Structural impact: the Forum is replanned around Caesar's buildings. What you see today: the Curia, the most complete building on the site.
6. End of the Republic — the Forum is already insufficient to serve as the city's administrative and representative centre. Structural impact: the imperial fora are built elsewhere; here the emperors add only monuments of prestige. What you see today: why this square is surrounded by temples and arches rather than offices.
7. 1st–2nd centuries AD — the Temple of Vespasian and Titus and that of Antoninus Pius and Faustina go up, dedicated to the memory of deified emperors. Structural impact: temple fronts close the western end. What you see today: three columns standing alone, and a temple front embedded in a later church.
8. 203 AD — the monumental Arch of Septimius Severus is built at the western end of the square to celebrate the emperor's victories over the Parthians. Structural impact: a triple arch across the end of the Forum. What you see today: it, nearly complete.
9. Early 4th century — the last great intervention, by Maxentius: the Temple dedicated to the memory of his son Romulus and the imposing Basilica on the Velia. The reign of Constantine the Great sees the last major expansion. Structural impact: the largest vaults on the site. What you see today: three enormous coffered bays at the eastern end.
10. 608 AD — the Column in honour of the Byzantine emperor Phocas is raised. Structural impact: a single column on the paving. What you see today: the last monument ever built in the Forum, nine centuries after the valley was drained.
11. Later — much economic and judicial business had already transferred to Trajan's Forum and the Basilica Ulpia to the north. Structural impact: the Forum ceases to be the working centre. What you see today: a square that outlived its function by centuries before it became a ruin.

The Palatine

1. Iron Age — settlements on the hill belong to the most ancient nucleus of the city of Rome. What you see today: the oldest stratum on the site.
2. 2nd–1st centuries BC — the hill becomes the residential quarter of the Roman aristocracy, with exceptional painted and floor decoration such as the Casa dei Grifi, and holds important cults including the Magna Mater, Cybele. What you see today: painted rooms under later floors.
3. From Augustus — Augustus symbolically chooses the hill for his own dwelling, including the Casa di Livia; the Domus Tiberiana, Domus Transitoria, Domus Aurea and finally the Imperial Palace — Domus Flavia for representation, Domus Augustana for Domitian — follow. What you see today: terraces of brick substructure, and the reason every European language calls a grand house a palace.