Earth-2021358

Earth-2021358, also known as the Marvel Cinematic Universe, is a shared universe between many Marvel films first released in 2008.

Production
In the 1990s, Marvel went bankrupt and thus were unable to make their future films, being forced to give away the film rights to different film companies such as Sony given the rights to Spider-Man and Fox given the rights to X-Men and the Fantastic Four.

In 2005, Marvel was met with Merril Lynch and they agreed to make a film based on The Avengers and to at first introduce these heroes separately as Marvel didn't give away the rights to Iron Man, Captain America, or Thor, as their rights bounced around with failure to make these films from other companies, and thus they agreed and decided to make Iron Man their first film to make it based around the team's leader though it was a challenge since the character wasn't very popular at the time.

As well, another problem would be that Marvel needed to have Avenger Hulk, though his rights were taken by Universal Studios, however following the cancellation of the sequel to 2003's Hulk, Marvel and Universal collaborated on The Incredible Hulk which was made due to Hulk 2 cancellation and since the Hulk was much more popular than Iron Man at the time, and with Louis Leterrier directing the project to make up for the fact that he was unable to direct Iron Man.

Despite the Hulk being more popular than Iron Man, Iron Man was more successful than The Incredible Hulk critically and Box-Office.

Meanwhile, in 2006 at the same time Jon Favreau was working on Iron Man, Edgar Wright helped work on Ant-Man, which was being made before Iron Man and thus needed a rewrite to fit into the continuity. Matthew Vaughn meanwhile was working on a Thor film with an attached release date for 2010 though it was pushed back to 2011 due to Ant-Man's release. Captain America's release from 2008 was pushed back since Jon Favreau left the project to direct Iron Man though Joe Johnston approached Marvel to direct the film.

It was released in 2011 with filming in 2010. After all of these films, The Avengers was released in 2012 with all of these characters as well as Ant-Man character Hope van Dyne becoming the Wasp as teased in that movie's post-credit scene.

As well some time in 2010, following the cancellation of Sony's Spider-Man 4 the rights were reverted to Marvel though the companies were forced to collaborate and thus The Amazing Spider-Man was released in 2012 now starring Tom Holland as Spider-Man. Sony was left with thinking of a film on their own though it would not be made until Marvel would return to help with the project.