In Afghanistan, Tony Stark is kidnapped by the terrorist group the Ten Rings. He develops the Iron Man armor to escape. (Iron Man)
Three months later, Tony returns to the United States and orders his company to stop making weapons. (Iron Man)
Tony learns his associate, Obadiah Stane, secretly arms the Ten Rings, and in fact arranged Tony’s kidnapping, which actually was suppose to be an assassination. (The Ten Rings demanded ransom when they realized their target was Tony Stark) Stane develops his own Iron Monger suit and fights Iron Man in California. (Iron Man)
That night Stark meets S.H.I.E.L.D. agents and give him his alibi to cover for being Iron Man, which of course he doesn’t follow. The S.H.I.E.L.D. division that covers up superhuman events is called Damage Control. (Iron Man; Fast Friends, exclusive digital comic on Marvel.com)
The next day, Tony Stark holds a press conference. He does not follow script and reveals he is Iron Man. (Iron Man)
That night Nick Fury visits Tony at home and talks about the “Avengers Initiative.” (Post Credit Scene, Iron Man)
Anton Vanko watches Tony’s press conference on Russian TV and tells his son that (Iron Man) should have been you. He dies, but not before passing on his knowledge and documents to his son. (Iron Man 2)
Agent Coulson single-handedly stops a rouge airman at a Shield Base. (Iron Man 2 Agent Coulsen, exclusive Digiital comic on Marvel.com)
Agent Coulsen helps train a new S.H.I.E.L.D. agent, during which it’s revealed the Ten Rings group never attacked American soil. (Iron Man 2 Agent Coulsen, exclusive Digiital comic on Marvel.com)
S.H.I.E.L.D. agents attack a ship in Yemen that has been commandeered by the Ten Rings group. Iron Man arrives unexpected and helps the S.H.I.E.L.D agents. It is revealed that Tony keeps tabs on Fury, just as Fury keeps tabs on him. (Iron Man 2 Nick Fury, exclusive Digital comic on Marvel.com)
6 months after the Tony reveals he is Iron Man, Ivan Vanko (as Whiplash) and Justin Hammer conspire to kill Iron Man and destroy the Stark legacy. During which James Rhodes dons suit of armor to help his friend Tony, basically becoming War Machine.(Iron Man 2)
Around this time the events of Thor occur, where Thor is banished from Asgard as punishment for is arrogance and foolhardiness. He is separated from his hammer until he becomes worthy to hold it again. He then battles dark forces that threaten Asgard, and to some degree, Earth. (Thor)
At some unknown time Nick Fury encounters Bruce Banner at a bar, and witnesses him transform into the Hulk. Hulk escapes. Fury determines Hulk is not the Super-solider they want, and orders S.H.I.E.L.D. not to pursue him any further. General Ross alone will pursue Banner. (Nick Fury: Director of Shield. Exclusive Digital Comic on Marvel.com)
The Hulk fights the military at Culver University in Virginia, including the soldier Emil Blonsky. (HULK)
(Note, the Hulk movie came out the same summer as the first Iron Man, two years before Iron Man 2. However, it takes place just after Iron Man 2. News footage from the Hulks Rampage at Culver University is shown at the end of Iron Man 2)
Tony is offered an advisory position on the coming Avengers team. (Iron Man 2)
Bruce Banner encounters Samuel Sterns in New York city. Stern attempts to cure Hulk, but his lab is raided by the military. Banner is captured, only to be released to fight Emil, who has turned to Abomination. Stern’s himself also appears to get infected with Gamma blood and Hulk escapes. (Hulk)
After the Hulk fights Abomination, Ross drinks at an officer’s bar, distraught over losing Hulk again. Tony Stark arrives and tells him about a secret team being formed. (Hulk)
One year after the events of Iron Man 2, Thor, and Hulk, Captain America is found in the arctic and revived. (Captain America: The First Avenger).
Just after Captain America is revived, he is recruited by SHIELD along with Iron Man, Thor, Hulk, Black Widow and Hawkeye to join the Avengers. Together they stop Loki from conquering Earth. After this adventure Thor takes Loki back to Asgard to face Asgardian justice, and Hulk, Captain America, and Iron Man are allowed to go their separate ways.
During the Christmas season following the formation of the Avengers, a terrorist called the Mandarin launches terrorist attacks against the United States. The Mandarin is also involved with a scientific think thank called Advanced Idea Mechanics. They are soon defeated by Iron Man and War Machine/Iron Patriot. (Iron Man 3)
Note this Timeline uses information primarily from the Marvel films, with promotional materials and digital comics secondary. At this time I’m not including most video game tie-ins, as to the best of my knowledge are not reflective of film continuity. I’m also not including the film novelizations, as their information can be contradictory over time.
Also a promotional website says the new Stark expo is in 2010, most movies are assumed to take place the year they come out, however this can grow complicated with sequels. On Joinsheild.com for example, the viral website for Thor, the date of the hammer falling to earth is April of 2011, but it’s known to take place during Iron Man 2. Hence, until I hear otherwise I’m not assigning specific dates to the movies.