In the model of theatre space of the Italian Baroque, the proscenium arch limits the audience’s view, framing the stage as a picture. It not only hides the technical apparatus of the stage – it makes invisible all backstage labour.
The spatial model of the Baroque court theatre had a central axis, with the audience looking along it one way, and the performers the other, framed by the proscenium. The arch itself was a rectangular structure that separated the auditorium from the stage – a frame through which the audience observed the event. It produced a sense of depth and allowed the perspective scenery to create a three-dimensional illusion of a fictional space, within which the action of the play could take place. This concept derived from the perspectival method drawing that developed in the Renaissance period. The first documented appearance of the arch was 1585 in Vicenza, Italy, in the Teatro Olimpico (J.03, Q650). The oldest intact arch still in use is in Parma in the Teatro Farnese (H.04, Q7847).
The later concept of the invisible fourth wall of the theatre stage can be considered as a social and conceptual construct which divides the actors and their stage-world from the audience which has come to witness it. But since the curtain usually comes down just behind the proscenium, it also has a physical reality when the curtain falls, hiding the stage from view.
While the sides and top of the proscenium frame became an important feature of European theatres through the 18th and 19th centuries, often becoming very large and elaborate, the proscenium front below the stage – the bottom edge of the picture frame – became plainer. The introduction of an orchestra pit for musicians during the Baroque era devalued the proscenium frame, bringing its bottom edge forward to the front of the pit, where a barrier, typically in wood, screened the musicians. The result was the framing proscenium arch – sides and top only.
The proscenium arch frames the fictional world of the performance, making it clear to the audience what is in that world and what is not. The proscenium therefore also masks the wings, overhead and substage mechanics that provide for scene changes, lighting, and so on. In his 1640 book Recreational Architecture (Q61), Josef Furttenbach writes about how to light the stage, saying oils lamps can be placed ‘within the scene, above between the clouds, at both sides, and in the front and rear pits, all of course completely concealed.’ The phrase ‘of course’ here is telling – Furttenbach knows his readers will understand the imperative to hide the lamps. The light must be visible, but its source must not – that is the fundamental conceit of the illusionistic stage, which dominated Western ideas of theatre from the Renaissance until the early 20th century, and is still influential today.
The conventions related to the proscenium arch have been increasingly challenged since the start of the 20th century. The Festspielhaus, Hellerau (E.06, Q63) radically reimagined performance space, with no proscenium, and no pretence of a fictional world, with audience and performers sharing a single room. Mainstream theatre underwent a more gradual change: the 1960 premier of the musical Oliver! is believed to be the first production in London’s West End to expose the overhead lighting rig, with no masking. To meet his political aims, Bertolt Brecht’s actors would ‘break the fourth wall’, addressing the audience directly as part of the dramatic action.
The staging of rock and pop concerts has gone a step further – the technical apparatus of lighting, sound, video and rigging has become the scenography. Speaker stacks, once carefully hidden in theatres, are now proudly displayed, while truss rigs are artfully designed, part of a mobile architecture of space and light (A.09). This aesthetic has sometimes found its way back into theatre, in particular in rock musicals but even occasionally in opera. The proscenium arch is often no longer a frame to the dramatic picture, but an important signifier – something built specifically as part of the scenography of the individual production, not as part of the building’s architecture. Here, the proscenium tells us that what we are looking at is not just theatre, it is deliberately and overtly theatrical.
Within this rich variety of ways of staging, one legacy of the proscenium concept remains: the expectation that the backstage staff in the theatre should be out of view. With only very occasional and carefully controlled exceptions, technicians, stage managers, dressers and others must not be seen. The result is a lack of recognition – a kind of professional invisibility – in which backstage labour can be undervalued and disregarded not only by audiences, critics and scholars, but also by other theatre workers and employers.