A long time ago, I talked about Tin, the Metal Man who was arguably the bravest character in the Silver Age, because he always showed great valor despite obviously lacking an iota of self-confidence.
At the opposite end of the spectrum was Volstagg the Voluminous, a Marvel hero who first appeared in the Tales of Asgard backup feature in Journey into Mystery #119:
It is somewhat remarkable that Volstagg is shown fighting in his initial appearance, as he generally avoided combat whenever possible:
All the while blustering about what a mighty warrior he was.
The Tales of Asgard feature, which had started as a way for Stan to work in some background on the Norse gods, rapidly evolved into the adventures of the Warriors Three: Volstagg, Hogun the Grim and Fandral the Dashing (with Thor often joining in):
Hogun looks a bit like Attila the Hun, and Fandral was inspired by Errol Flynn's version of Robin Hood (and would later inspire Green Arrow's extreme makeover).
Volstagg himself was based on the character of Falstaff, who appeared in three Shakespeare plays, most notably the two parts of Henry IV. In the first part, Falstaff is the drinking and debauching companion of Prince Hal (the future Henry V). Like Volstagg, he's portly and given much to braggadocio, and is the frequent subject of the jests of his companions. Thor himself can be seen as similar to Hal; the son of the King who sorely tests his father's patience yet shows great heroism. Falstaff is repudiated by Hal in the final scene of the second part of Henry IV, as a sign that the young prince has renounced his former dissolute lifestyle and is ready to assume his duties as king. As far as I know, Thor never similarly abandoned Volstagg.
One aspect of Volstagg's characterization must be commented on, and that is his steed. While Hogun and Fandral had sterling and mighty chargers, Volstagg was given a mount that would not seem capable of supporting his girth:
This further emphasizes the comical nature of the character.