If you’ve ever walked by a frame shop in New York City, you’ve inevitably seen a “Keep Calm and Carry On” poster in the window. But for the thousands of college students that bought one for their dorm room, I guarantee none of them know the story behind it. Until now.

The following short film by London-based filmmaker Temujin Doran traces the poster’s origins from the beginning of World War II to its rediscovery in an English bookshop in 2000. Although we will probably never know who the artist was responsible for its simple and timeless design, it is without a doubt one of the most iconic images of the 20th century.