A forum (Latin forum "public place outdoors", plural fora; English plural either fora or forums) was a public square in a Roman municipium, or any civitas, reserved primarily for the vending of goods; i.e., a marketplace, along with the buildings used for shops and the stoas used for open stalls. Many forums were constructed at remote locations along a road by the magistrate responsible for the road, in which case the forum was the only settlement at the site and had its own name, such as Forum Popili or Forum Livi.
The functions of a forum
In addition to its standard function as a marketplace, a forum was a gathering place of great social significance, and often the scene of diverse activities, including political discussions and debates, rendezvous, meetings, et cetera. In that case it supplemented the function of a conciliabulum.
Every municipium had a forum. Forums were the first of any civitas synoecized whether Latin, Italic, Etruscan, Greek, Celtic or some other. The first forums were sited between independent villages in the period, known only through archaeology. After the rise of the Roman Republic, the most noted forum of the Roman world, the Roman Forum in Rome itself, served as a model of new construction. By the time of the late Republic expansions refurbishing of the forums of the city had inspired Pompey Magnus to create the Theatre of Pompey in 55 BC. The Theatre included a massive forum behind the theatre arcades known as the Porticus Pompei (Colonnades of Pompey). The structure was the forebearer to Julius Caesar's first Imperial forum and the rest to follow.