She was a Jewish girl from the Bronx, and he was raised Episcopal on Manhattan's Upper West Side. Together they made some of the greatest film noir movies the world had ever seen, and their May-December romance will go down in history as one of Hollywood's most glamorous marriages.

Lauren Bacall, 19, was a former model starring in her first leading film role when she met Humphrey Bogart, 45, on the set of To Have and Have Not in 1944. Bogart was married to his third wife, actress Mayo Methot, at the time. Despite their 25-year age gap, sparks flew between the two stars, and their relationship progressed quickly. The movie debuted on Jan. 20, 1945, and Bogart was divorced soon after. He and Bacall tied the knot on May 21, 1945 at a ceremony on Pulitzer Prize-winning author Louis Bromfield's farm in Lucas, Ohio. They would go on to have two children together, staying married until Bogart's death in 1957.

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Bogart and Bacall on their wedding day

Bacall wasn't the least bit interested in her future husband the first time she saw him on screen in Casablanca. The friend she saw the movie with found him sexy. "I thought she was crazy," Bacall toldVanity Fair in 2011.

When they met in person a few years later, her first impression of him was of a cordial, polite, and friendly man. He told jokes to make her feel more comfortable in front of the camera, and soon their working relationship became a flirtatious friendship. In her memoir Be Myself, Bacall recounted how, three weeks into filming, Bogart stopped by her trailer to say goodnight. She was brushing her hair, and he was standing behind her:

Suddenly he leaned over, put his hand under my chin, and kissed me. It was impulsive—he was a bit shy—no lunging wolf tactics. He took a worn package of matches out of his pocket and asked me to put my phone number on the back. I did. I don't know why I did, except it was kind of part of our game. Bogie was meticulous about not being too personal, was known for never fooling around with women at work or anywhere else. He was not that kind of man, and also he was married to a woman who was a notorious drinker and fighter. A tough lady who would hit you with an ashtray, lamp, anything, as soon as not.

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Bacall and Bogart at home with their pet dog in 1945

When director Howard Hawks got wind of the affair, he tried to put a stop to it by telling Bacall it was just a fling, that Bogart would dump her once filming ended. He even threatened to ruin her career, bluffing that he would send her to the "lowest" studios in Hollywood. "[Hawks] used to say to Bogie, 'You don't have to get serious about this girl. Take her downtown to a hotel and get a room with her—that's enough.' That was not Bogie's scene at all," Bacall revealed decades later.

Her mother disliked her new boyfriend, too. When she came to visit Bacall, she mused out loud about what her daughter was thinking by pursuing a married man 25 years her senior who had a drinking problem, according to Biography.com.

Of course, no one successfully deterred the union. Bogart became a father for the first time at age 46 when the couple welcomed their firstborn, a son they name Stevie—presumably after Bogart's character Steve in To Have and Have Not—in January 1946.

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Bacall and Bogart with Stevie, circa 1950

Their daughter, Leslie, was born on August 23, 1952. Following the success of their first film together, credited in large part to their onscreen chemistry, the pair was cast in the film noir movie The Big Sleep almost immediately after. They also starred in Dark Passage (1947) and Key Largo (1948) together.

Though their relationship was marred by mutual infidelity—his with his longtime hairdresser Verita Peterson, and hers with Frank Sinatra—their mutual deep care for each other was evident until the end.

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"I never believed that I could love anyone again, for so many things have happened in my life to me that I was afraid to love," Bogart wrote in a love letter to Bacall at the beginning of their relationship. "Now I'm afraid that you'll become impatient and that I'll lose you—but even if that happened, I wouldn't stop loving you."

Bogart died of esophageal cancer in 1957. Bacall got engaged to Sinatra shortly after, but the relationship ended after she talked publicly about their affair against his wishes. She married actor Jason Robards in 1961, though it seems she never really got over Bogie. Even her second spouse referred to her as "The Widow Bogart."

"No one has ever written a romance better than we lived," she wrote in her memoir. After her death on Aug. 12, 2014, she was interred at Forest Lawn Memorial Park in Glendale, California, the same cemetery as Bogart.