Star Wars is first released in theaters.

On this day in 1977, Memorial Day weekend opens with an intergalactic bang as the first of George Lucas’ blockbuster Star Wars movies hits American theaters.

The incredible success of Star Wars–it received seven Oscars, and earned $461 million in U.S. ticket sales and a gross of close to $800 million worldwide–began with an extensive, coordinated marketing push by Lucas and his studio, 20th Century Fox, months before the movie’s release date. “It wasn’t like a movie opening,” actress Carrie Fisher, who played rebel leader Princess Leia, later told Time magazine. “It was like an earthquake.” Beginning with–in Fisher’s words–“a new order of geeks, enthusiastic young people with sleeping bags,” the anticipation of a revolutionary movie-watching experience spread like wildfire, causing long lines in front of movie theaters across the country and around the world.

With its groundbreaking special effects, Star Wars leaped off screens and immersed audiences in “a galaxy far, far away.” By now everyone knows the story, which followed the baby-faced Luke Skywalker as he enlisted a team of allies–including hunky Han Solo and the robots C3PO and R2D2–on his mission to rescue the kidnapped Princess Leia from an Evil Empire governed by Darth Vader. The film made all three of its lead actors overnight stars, turning Fisher into an object of adoration for millions of young male fans and launching Ford’s now-legendary career as an action-hero heartthrob.

Star Wars: The Empire Strikes Back is released in theaters.

The Empire Strikes Back is a 1980 American epic space opera film directed by Irvin Kershner. Leigh Brackett and Lawrence Kasdan wrote the screenplay, with George Lucas writing the film’s story and serving as executive producer. The second installment in the original Star Wars trilogy, it was produced by Gary Kurtz for Lucasfilm Ltd. and stars Mark Hamill, Harrison Ford, Carrie Fisher, Billy Dee Williams, Anthony Daniels, David Prowse, Kenny Baker, Peter Mayhew and Frank Oz.

The film is set three years after Star Wars. The Galactic Empire, under the leadership of the villainous Darth Vader and the Emperor, is in pursuit of Luke Skywalker and the rest of the Rebel Alliance. While Vader chases a small band of Luke’s friends—Han Solo, Princess Leia Organa, and others—across the galaxy, Luke studies the Force under Jedi Master Yoda. When Vader captures Luke’s friends, Luke must decide whether to complete his training and become a full Jedi Knight or to confront Vader and save them.

Following a difficult production, The Empire Strikes Back was released on May 21, 1980. It received mixed reviews from critics initially but has since grown in esteem, becoming the most critically acclaimed chapter in the Star Wars saga; it is now widely regarded as one of the greatest films of all time.The film ranks #3 on Empire’s 2008 list of the 500 greatest movies of all time. It became the highest-grossing film of 1980 and, to date, has earned more than $538 million worldwide from its original run and several re-releases. When adjusted for inflation, it is the second-highest-grossing sequel of all time and the 13th-highest-grossing film in North America. The film was followed by a sequel, titled Return of the Jedi, which was released in 1983.

In 2010, the film was selected for preservation in the United States’ National Film Registry by the Library of Congress for being “culturally, historically, and aesthetically significant.”