Construction of the complex commenced in the first year following the establishment of the Roman colony, financed entirely through public funds. From their inception, the baths were closely associated with civic authority and were regularly frequented by members of the municipal elite. Following the seismic event of circa 62 CE, the structure sustained damage but was promptly restored—an indication of its functional and symbolic significance within the city. By the time of the eruption in 79 CE, the Forum Baths were the only bathing facility in Pompeii known to have remained operational.

circa 80 BCE

Samnite Period
There is no confirmed evidence of a bathing complex on the site during the pre-colonial Samnite period (before 80 BCE). The area north of the Forum was already urbanized, but the construction of the Forum Baths postdates the Republican-era Stabian Baths, which served the earlier community.

Early Roman Period
The Forum Baths were constructed shortly after the establishment of the Roman colony (circa 80–70 BCE) under Sulla in 80 BCE. Built with public funds, the complex reflected Roman architectural planning and civic infrastructure priorities. The layout included fully segregated male and female sections, independent entrances, and the complete sequence of bathing chambers. The building occupied an insula directly facing the Temple of Fortuna Augusta.

Late Republican to Augustan Period
During this time (70–27 BCE), the Forum Baths became one of the principal bathing facilities in the city. Architectural details such as stucco decorations, vaulted ceilings, and separate water supplies suggest continuous maintenance and civic patronage. The male section had multiple entrances from three adjacent streets (Via del Foro, Via delle Terme, and Vicolo delle Terme), integrating the complex into Pompeii’s evolving street grid.

Early Imperial Period
During the early Imperial period (27 BCE–circa 62 CE) the baths continued to operate, with minor renovations. They remained smaller in size compared to the Stabian Baths but strategically positioned for easy access by the elite and magistrates who frequented the adjacent Forum. Modifications included interior decoration updates and possible improvements to heating systems.

Post-Earthquake Phase
Following the destructive earthquake of 62 CE (circa 62–79 CE), the Forum Baths underwent prompt repairs, unlike the Stabian and Suburban Baths, which remained partially or wholly closed. Structural reinforcements and restorations ensured that the Forum Baths were the only fully functional public baths in the city by the time of the eruption. Archaeological traces confirm that the heating system, roof vaults, and decorative schemes were either restored or maintained during this phase.

Eruption of 79 CE
At the moment of the eruption, the Forum Baths were in active use. Finds such as bathing utensils, furnishings, and wall deposits confirm that both the male and female sections were operational. The complex was preserved in relatively good condition, allowing modern archaeologists to reconstruct its functional and architectural history in detail.

circa 80 BCE

Layout
Despite their modest scale, the Forum Baths were architecturally and functionally complete, containing all standard elements expected in Roman thermae. The complex was divided into separate men's and women's sections, each with independent access points. Three doorways, opening onto surrounding streets, provided entry to the men's quarters, though their designation as entrance or exit remains uncertain. A narrow corridor from Via delle Terme gave direct access to the apodyterium (changing room), while additional entrances from Via del Foro and Vicolo delle Terme led through a porticoed courtyard, a transitional architectural feature common in public bathing complexes.

The apodyterium most likely featured wooden cupboards or lockers (armaria) for the storage of garments and stone benches arranged along the perimeter. Its roof was a barrel vault pierced by a lunette skylight, while both vault and walls were once adorned with stucco reliefs against a yellow painted background, of which only fragmentary remains are extant.

From the apodyterium, bathers proceeded to the frigidarium (inspect), the chamber designated for cold bathing. This room was square in plan, illuminated by an oculus in the vaulted ceiling. It was architecturally circular and enriched with apsidal niches in the corners, and at its center was a circular plunge bath accessed by steps, conforming to conventional Roman design.

The tepidarium (inspect), accessed via a separate doorway from the changing room, offered a warm bath. Heating was achieved through a bronze brazier, and the room featured a barrel-vaulted ceiling. The walls were embellished with stucco reliefs, notably flanked by figures of telamones (inspect) supporting an ornamental shelf—a decorative motif reflecting Hellenistic influence.

The bathing sequence culminated in the calidarium, where users immersed themselves in hot water. A marble labrum (inspect), positioned against the far wall, provided cold water for cooling off. Thermal regulation was facilitated through hypocaust heating, with hot air circulating within hollow wall cavities lined with tegulae mammatae (concave, nipple-like tiles designed to increase thermal retention). The furnace room, situated adjacent to the calidarium, housed the boilers that supplied hot water for the entire complex.

The women's section of the forum baths was structurally analogous and located on the opposite side of the furnace room, which served both wings. Access to the women's area was also provided from Via delle Terme.

circa 80 BCE

Dedicatory Travertine Plaque (A)
According to Fiorelli, a title repeated in two travertine slabs, found within the building, but in a different place from the one where it was previously located, the names of the duumvirs and of the aediles who presided over the work, carried out by decree of the decurions at public expense. The plaque reads

L CAESIVS C F D V I D
C OCCIVS M F IIV
L NIRAEMIVS A F
D D S EX PEQ PVBL
FAC CVRAR PROB Q.