There is no more beloved American film than Casablanca (1943). In 1989 Casablanca was selected for inclusion on the National Film Registry, a designation reserved for films considered to be “culturally, historically, or aesthetically significant.” The film has also been mentioned prominently on programs like The American Film Institute’s 100 Years…100 Movies, and in 2006 The Writers Guild of America placed Casablanca‘s screenplay at the top of its best-ever list. Film critic Roger Ebert noted that Citizen Kane (1941) was the more respected and accomplished film, but he and audiences treasured Casablanca as the characters in it were all so noble. The final arbiter of a movie’s popular and industry success, the presentation of an Academy Award, is also part of Casablanca’s history: it won the Oscar for Best Picture, Best Director (Michael Curtiz), and Best Screenplay.

Casablanca was produced by Hal B. Wallis for Warner Bros. and premiered in New York on November 5, 1942, with a general release date of January 23, 1943. None of the top brass at Warners had great expectations for the film, other than a clever premiere date timed to roughly coincide with the Allied Forces invasion of North Africa (code named Operation Torch). The cast was all A-list, but this would be Humphrey Bogart’s first romantic leading role, and the script, based on an unrealized stage play, was being written as the production carried on. As with all studio productions during the glory days of the great Hollywood studios, when a picture was completed, the original camera negative (the film in the camera at the time of the on-set shooting) was “protected” by making two fine-grain master (master positive) copies. In this case, Casablanca was made during the nitrate film era, and each fine-grain master (FGM) was deposited in the dedicated Warner Bros. film labs on the East and West coasts. The vintage 35mm FGM held in West Coast storage currently resides at the UCLA Film and Television Archive, but now only three reels exist due to nitrate decomposition. The best, earliest surviving and complete material for this iconic film is the 35mm nitrate FGM in the MoMA Department of Film collection.

The MoMA FGM of Casablanca was produced 70 years ago on 1942 Kodak nitrate film stock and printed from the original negatives, with the exception of an inserted tail section of reel #5, which reflects inferior 1950s footage. (There is a slight bouncing motion in the image that was printed in from this mid-century source material.) But overall, the MoMA FGM is a luminous vision of the black-and-white feature and truly the closest material to the original that was shot when Bogart and Bergman walked on the set.

The function of the FGM is to act as a direct copy and protection for the 35mm camera negative after it was edited with the sound and effects inserted. Also, the strategy of depositing an FGM on each coast provided yet another level of insurance for the studio in case of fire, theft, or any other loss. Warner Bros. was not in the business of protecting these materials for long-term preservation care at the time; rather, they aimed to get the most use out of the materials for the first-run distribution market. Due to the extensive audience popularity of Casablanca and an official studio re-release in 1949, the original 35mm nitrate negative was worn out from making print after new print. The burgeoning demand for movies on broadcast television further taxed original negatives, often leaving them damaged, with tears and splices. In the late 1980s, as part of a larger donation, Turner Entertainment, the parent organization of Warner Bros., gave MoMA a vast collection of nitrate materials, including many treasures of American cinema. Films such as All This, and Heaven Too (1940), Angels with Dirty Faces (1938), High Sierra (1941), and Jezebel (1938), along with the unique Casablanca FGM, entered the collection for long-term preservation purposes.

When founding Department of Film curator Iris Barry visited Hollywood in the 1930s, she knew that to establish and grow a museum film collection with depth and focus, she also needed the film industry’s generosity and long-term interest. This collaboration between the major film studios and the international film archive community remains in place today, the repositories of the materials the studio had decades earlier deemed of no further use. As technologies change and the film industry revisits their classic libraries for contemporary distribution products, limited and controlled access to original materials such as nitrate prints, negatives, or even an FGM is sometimes possible. When home video distribution took hold in Hollywood at the end of the 20th century, it also meant requests to access unique materials like the Casablanca FGM were directed to the film archives around the world. Returning to the nitrate FGM under close supervision by MoMA, Warner Bros. had excellent source material from which to generate their then video copies—as well as current digital versions. This situation was not a collaboration limited to MoMA, but rather became a commonplace practice experienced by film archives who engaged with film studios. It’s curious how an outmoded film stock (nitrate) and a late-19th-century invention (motion picture) combine to remain the best possible source materials for 21st-century digital technology. This scenario is not unique to Casablanca or MoMA, as international film archives count among their collections film materials of equal rarity and aesthetic value, rescued from a time when the nitrate film elements were thought to be obsolete.

When the lovers Rick and Ilsa part at the end of Casablanca, they try to find comfort in the closeness they  once shared. Ilsa realizes their separation will be permanent and begins to cry. Rick says, with genuine affection and in an attempt to sooth Ilsa’s heartache, “We’ll always have Paris.” We’ll also (almost) always have a 35mm nitrate fine-grain master of Casablanca that reflects the original camera negative—as long as we continue to store it properly and access it for extremely limited preservation-related projects. Film materials stored under optimum cool and dry conditions could survive well in excess of 100 years, according to studies conducted by the Image Permanence Institute at the Rochester Institute of Technology.