My brother was a big comic fan when he was a kid so while I didn't read them I'm aware of the characters.  Don't remember Hawkeye though.  I'm very interested in this character.  Isn't the actor that plays Hawkeye also in the last Mission Impossible: Ghost Protocol?
Did you stay until after the credits ran?
		
		
	 
from wiki:
Clint Barton was born in 
Waverly, Iowa. At a young age he lost both of his parents in a car accident. After six years in an orphanage, Clint and his brother 
Barney ran away to join the Carson Carnival of Travelling Wonders.
[2] Clint soon caught the eye of the 
Swordsman, who took the young boy on as his assistant. Along with the help of 
Trick Shot, the Swordsman trained Clint to become a master archer.
[3]  Clint later found the Swordsman embezzling money from the carnival.  Before he could turn his mentor over to the authorities, Clint was  beaten and left for dead, allowing the Swordsman to skip town.
[4] Clint's relationship with his brother Barney and Trick Shot soon deteriorated as well.
[5]
 
Clint adapted his archery skills to become a star carnival attraction, a master archer called 
Hawkeye, otherwise known as “The World’s Greatest Marksman”. He spent some time as a member of 
Tiboldt's Circus,
[6] before joining the 
Coney Island Circus. He witnesses 
Iron Man  in action and is inspired to become a costumed hero. However, after a  misunderstanding on his first outing, Hawkeye is accused of theft and  believed to be a criminal. On the run, the naive Hawkeye meets the 
Black Widow, a spy for the 
Soviet Union, with whom he falls in love. Blindly following the Black Widow, Hawkeye aids her attempts to steal technology developed by 
Tony Stark.  In one of their battles with Iron Man, the Black Widow is seriously  injured. Hawkeye rescues her and flees the battle to save her life. But  before Hawkeye can take her to a hospital, the Black Widow disappears.  Hawkeye decides to be a "straight-shooter" from then on.
[7]