what was the first movie to launch in the mcu?
Iron Man.
Marvel Cinematic Universe

The first MCU film is "Iron Man" (2008), 
when do all the marvel movies take place 2008,2012,2013,2015,2016,2019 and 2021. what is the mcu? The Marvel Cinematic Universe (MCU) is an American media franchise and shared universe centered on a series of superhero films.
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Marvel Cinematic Universe [SEP] Introduction
Soundtrack albums have been released for all the films and many of the television series, as well as compilation albums containing existing music heard in the films. The MCU includes tie-in comics published by Marvel Comics, while Marvel Studios has produced a series of direct-to-video short films, called Marvel One-Shots, and a viral marketing campaign for its films and the universe with the faux news program "WHIH Newsfront".