This involved building the largest studio set in the then history of French cinema - the quarter mile of street frontage, reproduced in scrupulous detail, representing the Boulevard du Crime, the theater district of Paris in the 1830s and 40s. This would have been a daunting prospect at the best of times but in Vichy France, when all artisans, transport, materials, costumes and film stock were all in short supply, it was a miraculous achievement.
The film's title refers to the people who sat in the upper balcony of the theatre. This is where the lower classes sat, as the seats were significantly cheaper that the ones below (as noted in the film itself). It is the French equivalent of the term used in English theatres, "the gods."
Filming was completed a short time before D-Day and the director, having planned to distribute the film after the liberation of France, had three copies printed and concealed in three different places: a cellar of the Banque de France, a strongbox of Pathé and a Provence country house.
Several of the characters are based on real people: Frédérick Lemaître (1800 - 1876), noted French actor and playwright; Jean-Gaspard Deburau, or Debureau (1796 - 1846), a Bohemian-French actor and mime, performing at the Théâtre des Funambules; Pierre François Lacenaire (1800 - 1836) a noted French poet and murderer, and inspiration for Dostoevsky's Crime and Punishment; Victor Avril, a henchman of Lacenaire.
Garance says she grew up in Meilmontant. Menilmontant, known affectionately as "Ménilmuche", was part of the commune of Belleville, and is now a suburb of Paris, part of the city's 20th arrondissement. It was absorbed into the City of Paris in 1860.
The character, the Count de Montray, is inspired by the Duc de Morny - Charles Auguste Louis Joseph de Morny, 1st Duc de Morny (1811 - 1865), a French statesman and natural son of Hortense de Beauharnais and Charles Joseph, Comte de Flahaut, and thus half-brother of Emperor Napoleon III.
"L'Auberge Des Adrets", the play performed by Frederick in Part 2, was written by Benjamin Antier and performed for the first time in 1823, featuring the real Frederick Lemaitre. ' Robert Macaire' is a character in this play and in another play eponymously titled and performed in 1835.
The Horatti and Curatii are two families of ancient Latium. A war between two cities of Latium, Rome and Alba Longa, was to be decided by a combat between the three Horatii bothers (Rome) and the three Curatii brothers (Alba Longa). The Horatii won, but of the six combatants only one survived. A painting by Jacques Louis David portrays the Horatii before the battle.
While the real historical Lacenaire was awaiting execution he wrote an (almost finished) autobiography. It has been said (rightly or wrongly) that this is the first writing in which someone tries to explain his adult life by means of his childhood events. This autobiography is available in English translation.