Battle: Los Angeles tells a tale of an alien invasion that's somewhat thwarted by a group of U.S. Marines in California, and while it's a by-the-numbers military action film, it's actually inspired by a true story. Directed by Jonathan Liebesman (Teenage Mutant Ninja Turtles) with a script from Christopher Bertolini (The General's Daughter), Battle: Los Angeles stars Aaron Eckhart as USMC SSgt Michael Nantz, Michelle Rodriguez as USAF TSgt Elena Santos, Ramon Rodriguez as USMC 2ndLt William Martinez, and more.

At the start of the movie, 20 extraterrestrial spaceships land in the water outside major cities around the world, with one of those cities being Los Angeles. A platoon of Marines then accompanies a USAF technical sergeant throughout the city in search of the aliens' command center, which they end up destroying and forcing the invading aliens back, at least for a brief time. Of course, none of that ever really happened. So while there's never been an alien invasion before, a real-life event from the early 1940s did inspire the story that ultimately became Battle: Los Angeles.

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Shortly after the attack on Pearl Harbor in December 1941, the U.S. War Department assigned anti-aircraft regiments to San Diego, San Francisco, Seattle, and Los Angeles. And, understandably, before the Battle of Midway in the summer of 1942 (which is considered a turning point in the Pacific Theatre of World War II), the military was constantly on high alert on the west coast. In the end, there were no aerial attacks on the western seaboard, but there was one event that resulted in a massive anti-air bombardment that became known as the Battle of Los Angeles.

Battle Los Angeles

On February 23, 1942, a Japanese submarine attacked the area around Santa Barbara, CA, known as the Bombardment of Ellwood, which was crucial in causing an invasion scare throughout the rest of the state. A day later, on February 24, a warning was issued that there could be another attack by the Japanese, and that night, lights were spotted above Los Angeles. The military believed it was the Japanese and they quickly began an aerial barrage that lasted most of the night, with air raid sirens going off for hours.

Dubbed the Battle of Los Angeles, the air raid was front-page news throughout the entire country the next day, but despite thousands of people witnessing the same lights above the city that night, there wasn't any evidence to suggest that it was an attack by the Japanese. The event was later blamed on war nerves and the lights simply being a weather balloon. But since people started firing anti-aircraft artillery, everyone joined in, and they kept firing until an all-clear was given.

Of course, since no evidence could be supplied that the lights were, in fact, from a weather balloon, it was believed they came from an alien spaceship. Doctored photographs of the night didn't help the matter, and so, people believed - and some still do believe - it was a failed alien invasion. And so, the Battle: Los Angeles movie takes this one event and asks the question, what if it really was aliens? But, of course, that's where the true story inspiration stops and the fiction begins.

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