New Avengers: Illuminati (2006)

This one-shot is a direct link to the linewide Civil War event. It digs deeper into the origins of the Illuminati group, which we learn was formed by Iron Man, and tells the story via flashbacks.
He gathered them together to unite against common threats, and did so a long time ago–in the wake of the Kree-Skrull War.
We then get the full story of Hulk’s exile and proceed up to the Superhuman Registration Act. Reed and Tony want to encourage the super-communities to comply, while the rest of the group strongly disagrees. They quit the Illuminati in protest.

And so here we are, ready to start the Civil War event.

Amazing Spider-Man #529-531 (2006): Mr. Parker Goes to Washington
In the lead-up to Civil War, Peter Parker gets a new suit (armored) from Tony Stark. It makes him much more powerful and invulnerable to most of the street-level threats…
Astonishing X-Men #19–24 and Giant-Size Astonishing X-Men #1 (2006): Unstoppable
“Unstoppable” is Joss Whedon’s final story in this fantastic series, and after it the title goes on hiatus for about half a year. It concludes the Breakworld/”Colossus is the worldbreaker”…
HULK #92-114: Planet Hulk (2006-2007)
It must have been fun reading comics in 2006. “Events” weren’t a new thing, but amazing events kinda were. We got Annihilation and Planet Hulk in the same year. Wow….