The palace has had a rather troubled history. Even the origin of the name is uncertain: some believe that electoral meetings were held there in ancient Rome (hence "mons citatorius"); other sources suggest that the name came from the fact that waste material from the reclamation of the nearby Campus Martius ("mons acceptorius") was dumped there. The existing palace, built on the previous site of a group of humble dwellings, was commissioned from Bernini by Pope Innocent X as the future residence of the Ludovisi family.
But when the Pope died in 1655, work was suspended due to lack of funds and was only resumed more than thirty years later by the will of another Pope of the same name (Innocent XII), who first wanted to use the palace as a poorhouse and then decided to house the Apostolic Curia (papal courts) there.
In the meantime Bernini had died and the new architect Carlo Fontana made extensive changes to Bernini's project, retaining the characteristic convex façade but adding the airy wall belfry. By the Pope's will Fontana was obliged (again because of lack of funds!) to give up the idea of creating a single large square on the present sites of Piazza Colonna and Piazza Montecitorio. Pope Innocent's Curia was inaugurated in 1696 by turning on the water of the large fountain located at the far end of the large semi-circular courtyard. As well as the courts, the palace later housed also the seat of the Governorship of Rome and police headquarters, thus becoming the centre of the administrative and judicial life of the papal government.
The main bell (which is now rung only on the occasion of the election of the President of the Republic) marked the beginning of the audiences and its precision in tolling the hours became proverbial in Rome. Every Saturday the Roman people flocked to the square to see the drawing of the lottery numbers which, as Stendhal narrates in " Promenades dans Rome", were shouted from the balcony.
After the unification of Italy and the annexation of the Papal States in 1870, the transfer of the capital to Rome meant that suitable locations had to be found for the governing bodies of the Kingdom. For the Chamber of Deputies, after other solutions such as the Capitol and Palazzo Venezia had been rejected, the choice fell upon Montecitorio and the work to adapt the old palace to the new requirements was rapidly undertaken.
The task of building the assembly hall was entrusted to a comparatively unknown public works engineer, Paolo Comotto, who did the job very quickly (it was inaugurated in July 1871), constructing in the large courtyard a semi-circular hall with tiered seats supported by an iron framework entirely lined with wooden panelling. Although highly praised initially the new hall soon proved to be inadequate: its acoustics were poor, it was very hot in summer and very cold in winter, so much so that the President authorized the deputies to keep their hats on during particularly cold days. After an unsuccessful attempt to build a new parliament house in Via Nazionale (planned to house also the Senate), in 1900 the 'Quaestors' of the Chamber decided to close the Comotto hall and transfer parliamentary work to a small temporary hall that remained in function until 1918. Meanwhile the government had assigned to the architect Ernesto Basile the task of making extensions to the Chamber according to a project that was implemented by building a new construction at the back of the earlier one.
Basile, a leading representative of Italian Art Nouveau, retained only the front part of the ancient Bernini palace, squared the central courtyard, demolished the wings and the triangular-shaped rear section. He demolished the surrounding streets to make way for Parliament Square, erecting in the space thus created a large square building made of travertine and red brick with four mediaeval-like towers.
He achieved extremely interesting results in the interior of the building. Here, Basile displayed a designer's rather than an architect's tastes, obtaining an overall effect in which the solemnity of the rooms was in perfect harmony with the airiness of the decorations and the detailed work.
This is confirmed, as well as by the Plenary hall, also by the corridors and monumental rooms (in the first instance, the most famous, the "Transatlantic"), the committee rooms, the coloured marble paving, the ceilings, the decorations in the taste of the time that Basile concerned himself with down to the last details. The "Transatlantic", the large lobby situated at one end of the Plenary hall where MPs gather in the breaks between sessions, gets its name from the ceiling lighting typical of ocean liners.
Basile was assisted also by other artists, leading representatives of the ceremonious (and somewhat rhetorical) tastes of the time: Leonardo Bistolfi and Domenico Trentacoste, the authors of the marble groups and rear façade. Aristide Sartorio is the author of the large pictorial frieze on the history of the "Italian people" running around the upper section of the Plenary Hall, right below the delicate Art Nouveau stained-glass and iron velarium by Giovanni Beltrami.
The bronze panel
Davide Calandra is the author of the great bronze panel in the Plenary hall - "The Glorification of the Savoyard Dynasty".
The main reception rooms are located on the second floor, which also houses the President's offices and those of the Members of the Bureau and the Secretary General. A monumental staircase leads into the Corridor of the Busts. The corridor is lined with some thirty marble or bronze busts of distinguished MPs, from Cavour and Garibaldi to the most prominent figures in the parliamentary history of the Republic.
The Hall of the She-wolf, the largest room in the Bernini wing, gets its name from the presence of a bronze sculpture of the Roman wolf. The sumptuous room is further enriched by Flemish tapestries hung on the walls. The result of the institutional referendum held on 2 June 1946 was announced here and meetings of exceptional importance are still held here.
The President's Library opens on the left of the hall. It is here that the meetings of the Bureau and other governing bodies of the Chamber are held.
On the right is the Sala Aldo Moro. The naming of this historical room took place on 13 May 2008 in the presence of the President of the Chamber of Deputies Mr. Gianfranco Fini, and marked the thirtieth anniversary of the tragic death of the Apulian statesman. The room had formerly been known simply as the Sala Gialla (Yellow Room) in reference to its upholstery, and is furnished with High Baroque antiques from the Reggia di Caserta.