Seventy-six years ago — on November 26, 1942, in the midst of World War II — Casablanca, easily one of the best movies ever created, premiered in New York City.

Casablanca is the story of cynical American expatriate Rick Blaine and his one-time lover, Ilsa Lund. For those of you who haven’t seen it, the official film synopsis is as follows:

Rick Blaine (Humphrey Bogart), who owns a nightclub in Casablanca, discovers his old flame Ilsa (Ingrid Bergman) is in town with her husband, Victor Laszlo (Paul Henreid). Laszlo is a famed rebel, and with Germans on his tail, Ilsa knows Rick can help them get out of the country.

The movie has been, by any and all measures, an enduring and enormous success. It was the seventh highest-grossing film of 1943; it won the Academy Award for Best Picture, Best Director, and Best Adapted Screenplay; and the American Film Institute counts six lines from the movie on its 100 Years…100 Movie Quotes list, the most of any film.

There are countless reasons for the film’s success.

Among them is the subtle but masterful comedy, such as the tourists learning that the kindly man warning them about local pickpockets was himself a thief who just stole from them. Or when Vichy French Captain Louis Renault is ordered by a German major to shut down Rick’s nightclub, so he feigns outrage at “discovering” there is gambling in the club, only to be immediately presented with his own winnings from gambling.

There is also endless behind-the-scenes trivia for viewers to catch. One such example is the background of Conrad Veidt, who played the movie’s villain, German Major Heinrich Strasser. Veidt was an extraordinarily brave and principled man; as a German, he’d served in World War I, then returned home and starred in the film Different from the Others as a homosexual professional violinist — despite the fact that homosexuality was then criminalized in Germany. Different from the Others is believed to be the first ever pro-gay film; the movie was banned a year later, then ordered by Nazis to be destroyed.

When the Nazi Party began gaining power in Germany, Veidt falsely marked himself as Jewish on the required questionnaire in order to show solidarity with his Jewish wife and the increasingly persecuted German Jewish community. He was then forced to leave Germany for his own safety, and he gave his personal fortune to the British government to help fund the resistance.

Furthermore, he predicted that as a German actor he would be typecast in Nazi roles, and he therefore required that such roles be clearly shown to be the villains — while he used the paychecks from those roles to continue to help fund the war effort against the Nazis.

And then, of course, there’s the infamous duel of the anthems, between the French anthem “La Marseillaise” and German patriotic anthem “Die Wacht am Rhein.”

I would be unable to explain this scene any better than David Youngblood at the now archived website “Seven Inches of Your Time,” which called it “the greatest scene ever filmed” due to both its historical significance and its importance to the movie’s plot. I’ll include the most powerful and emotional sections, though I urge you to read it in full here. (Warning: Spoilers. Shame on you if you haven’t seen the movie already, though.)

The scene marks a major turning point in the film. Directly preceding this scene, the bar owner Rick (Humphrey Bogart) refuses to give or sell letters of transit to the war hero/revolutionary Victor Laszlo (Paul Heinreid). The letters of transit are the only hope of freedom for Victor, and his only chance at returning to his efforts at insurgency against the Nazis; Rick knows this, but is still too hurt and bitter that his lost love Ilsa (Ingrid Bergman) has chosen Victor over him. Rick’s refusal is essentially a Nazi victory, despite his careful attempts at framing his (in)actions as simple neutrality. The Germans, led by Major Strausser (Conrad Veidt), have established a de facto control over Casablanca, acting through the openly self-interested French Captain Louis Renault (Claude Rains).

After “La Marseillaise,” everything changes. … Everything kicks into gear, as now Rick, Ilsa, Victor, and Louis are all forced into unpleasant decisions that will push the film toward its climax.

And it all begins with the anthems. As Rick and Victor are ending their disagreement, they hear the German soldiers in the bar below, joyfully and triumphantly singing “Die Wacht am Rhein.” The rest of the bar is made up largely of refugees from the German war machine, so the anthem feels almost like taunting, a callous display of German power over people seeking to escape their conquering.

Victor reaches the band and immediately demands that they play “La Marseillaise,” the French national anthem. Here we see, for the first and perhaps only time, what has made Victor such an important figure. There’s such a fierceness to him, an intensity that comes bursting out as he repeats his demand — “Play it” — less than second after first making it.

The band leader looks first to Rick for approval. … Bogart’s nod is such a small gesture, but carries such enormous weight. This is the first moment of Rick choosing a side, of joining in resistance in some small way.

The band launches into “La Marseillaise” with Victor leading the singing, and within two seconds, the entire bar (except the Germans) has stood and joined him. … Within moments, “La Marseillaise” has drowned out “Die Wacht am Rhein.”

The story of Yvonne (Madeleine Lebeau) in Casablanca is perhaps the greatest example of economy in storytelling that I’ve seen. She appears in only three scenes in the entire film, with this one the last of them. Her total screen time combined is probably no more than a minute. And yet, in those brief stretches, we see an entire character arc play out; and what’s more, an arc that acts as a microcosm of the entire film.

There is such bravado in Henreid’s performance here; it’s the one scene where you can really see Victor as a revolutionary leader, capable of inspiring people into acts of defiance in the face of tyranny. When the camera reaches Ilsa again, her expression has softened, melted even, into one of love. A bittersweet love, perhaps, but an evident one. She knows that this reckless disregard for his own life is that same thing that once landed Victor in a concentration camp and threatens him again now in Casablanca, but that zeal must be the same reason she fell for him in the first place. Again, the economy of storytelling here is remarkable. Within a handful of seconds, an entire wordless story has been told: Ilsa’s sad resignation to their changing circumstances, Victor’s passionate defiance, and Ilsa’s acceptance of her husband, loving him for the fact that his greatest flaws are also his greatest virtues.

Ilsa’s acceptance is the final act needed for “La Marseillaise” to move on to reach its climax. Within less than just a couple of minutes, we have had the German aggression, Victor’s rebellion against it, Rick taking his first stand, the overwhelming passion of the French crowd, the redemption of Yvonne painting a story representative of the whole film, and Ilsa and Victor’s unconventional love in the face of adversity. All that remains is the final groundswell.

But that doesn’t even include perhaps the most touching aspect of the scene: Many of the actors and extras in the scene of the duel of the anthems were actual refugees of World War II, heightening the emotion and tension.

Yet perhaps the greatest thing in this scene is that most of the people in it weren’t actors at all; rather, director Michael Curtiz filled the scene with actual French refugees. Keep in mind, this movie came out in 1942 and was filmed at the height of World War II, at a time when Germany looked nearly unbeatable and Nazi occupation of France was indefinite. And here was a group of refugees from that occupation, given the chance to sing their anthem with defiant pride. For one brief moment, this wasn’t a movie. It was real life, and it was tragic, and it was brave. Reports have said that extras were crying on set during filming, and the passion is evident any time you look past the main actors to the background singers. Note, for instance, the furious arm pump by the man in the background behind the blonde woman at the left of the screen:

As  Youngblood noted, the movie itself was filmed and released during the war — filming began in May 1942 and finished in August 1942, and the film was released shortly after the Allies, including American troops, victoriously invaded North Africa.

Both the U.S. Holocaust Museum and the Auschwitz Memorial commemorated the day yesterday on Twitter. The U.S. Holocaust Museum praised the movie for its bravery in addressing the war, while the Auschwitz Memorial shared horrific Nazi crimes against Jews and prisoners that occurred the same day the movie premiered.

Such details as those listed above make it all the more striking to imagine how inspirational this film must have been for real-time war refugees and for people longing for freedom around the world contemporaneously.

And that’s just one more of the reasons why Casablanca remains among the best movies ever created.

 The views expressed here are those of the author and do not represent those of any other individual or entity. Follow Sarah on Twitter: @sarahmquinlan.