Hajime Isayama's Attack on Titan is one of the most popular anime and manga series, and it's only gotten bigger over the last few years with the series even getting a new live-action movie produced by Warner Bros.
But it started out in a much humbler place as Isayama once submitted his work, Humanity vs. Giants, to Shueisha's Weekly Shonen Jump but was rejected. Now fans can read that early work for free at the following link here.
Kodansha's Magazine Debut (via Anime News Network) recently published Isayama's original one-shot for Attack on Titan, Humanity vs. Giants, online. Isayama first submitted this one-shot to Shueisha's Weekly Shonen Jump magazine when he was 19 years old. Unfortunately, it was rejected. He then submitted the short manga to Kodansha's Magazine Grand Prix in 2006, and won the "Fine Work" award for the one-shot. The series eventually went on to be published in 2009 in Kodansha's Bessatsu Shonen Magazine, and the rest is history.
The one-shot is in Japanese, but many of the elements here should be recognizable to fans. Along with its early title, many of Isayama's early ideas have made it over to the final series. Humanity lives in a walled city to keep themselves safe from giant human eating monsters, and a boy joins a military force to help fight them.
Elements such as the maneuver gear, Titan fighting, and the main character's transformation into one of the giants all eventually make it into Isayama's work. Although this early work is rough, there are enough strong ideas here showing promise that it's no longer a mystery why Attack on Titan became one of the most popular series ever.
Attack on Titan was originally created by Hajime Isayama, and the series has since been collected into 23 volumes as of 2017. It's set in a world where the last remnants of humanity live within a walled city in order to escape the danger of the Titans, a race of giants monsters that eats humans. The lead character, Eren Yeager, ends up joining the military with his two childhood friends Mikasa and Armin after the Titans break through the wall and attack his hometown.
Now Eren, Mikasa, and Armin must survive in a world where they not only have the Titans to fear, but the very humans they are trying to save. You can currently find the series streaming on Crunchyroll, Funimation, and Saturday nights on Adult Swim's Toonami block.