In the show, Stephen Colbert assumes the role of, as he has explained in out-of-character interviews, a "poorly informed, high-status idiot"  , a parody of pundit show hosts found on American cable television news, in particular Bill O'Reilly , but also with influences from Joe Scarborough and Sean Hannity . Colbert has said the essence of what he felt the need to mock is summed up in a rule Scarborough claimed to adhere to: that he isn't doing his job if he lets his guest speak for more than seven seconds at a time without interruption. 
Colbert has said he also wants to capture some of the "folksiness" and love of his own monologue allegedly portrayed by CNN anchor Aaron Brown . When radio host Terry Gross interviewed Colbert on NPR 's Fresh Air , Colbert also cited Stone Philips , his first guest, as a major influence on his character, for his command of " gravitas ." 
Overall, the routine of the character Colbert assumes in the show is centered on egomania and reducing complex world affairs into ludicrously simplified soundbites or arbitrary conclusions, to humorous effect. In the premiere episode, Colbert denied that the show was all about him — even while simultaneously pointing out that his name appears all over the studio set and that his desk is shaped like a giant "C."
While still on The Daily Show the Colbert character admitted he had been born Ted Hitler. The Colbert character also claimed to have been in the United States Marine Corps until called on this lie, a reference to O'Reilly's claiming to have been "in combat."
Colbert is frequently shown to have worked in journalism for a long time. Occasionally footage is shown of him as a "young man" (usually with hilariously stereotypical 70's fashions) working an anchor at a local news station in South Carolina, still displaying his trademark outrage over minor municipal issues. It appears that in the fictional reality of the Colbert Report, Kevin Spacey performs the acting roles that the real Colbert has done, such as Chuck Noblet in Strangers With Candy .
It is sometimes implied that Stephen was much less of a square when he was younger, including numerous passing references to having first-hand familiarity with recreational drugs such as opiates , marijuana and cocaine as well as a reference to a wild back-packing tour across Europe .
Colbert jokingly claimed that, in the 1980's, he was briefly part of a glam rock band called "Stephen and the Colberts," of which he was the only member. The band's only song to date is entitled "Charlene (I'm Right Behind You)" in which Colbert stalks the woman (lyrics include "I think of you, when I dream of you, when I'm takin' pictures of you! I think of you when I'm in a blimp looking down from up above you!").
The Colbert character has a phobia of bears , which he refers to as "godless killing machines without a soul." In his interview with Gross, Colbert said that his character's fear of bears is based on his real life childhood nightmare of bears mauling him in his sleep. 
Most of the biographical details of the "real" Colbert are generally also used for the fictional one. Colbert mentions being born in South Carolina , being married, and having three children.
Interaction with guests
When the show premiered, the studio guests appeared to be uncertain and put off by Colbert's character. But by the fourth and fifth episodes, Colbert established a routine of remaining in character in a more affable way, and keeping his guest comfortable and in on the fun. One reviewer identified Colbert's on-the-spot ad libbing in character during the studio interviews as the one aspect of the show that was funniest and most indicative of (the actor) Colbert's true talent.