Irish-American comedian Conan O’Brien will take over Jay Leno’s post as the new host of NBC’s “Tonight Show” this upcoming Monday, June 1.

The former host of the immensely popular “Late Night With Conan O’Brien” is only the fifth person to take on the coveted spot, joining the ranks of comedy greats Johnny Carson and Leno.

He’s got some big shoes to fill, but luckily, O’Brien’s Irish Catholic background has helped prepare him for any comedic role.

O’Brien, 46, the third of six children, grew up in Brookline, Massachusetts watching Johnny Carson with his dad and performing comedy routines for his brothers.

“When all the writers are packed into [‘Late Night With Conan O’Brien’ head writer Mike] Sweeney’s office,” Conan told The New York Times Magazine, “it’s very comfortable for me, because that’s how I grew up. My older brothers, Neal and Luke, slept in twin beds, and I was in a cot at the foot of their beds. I loved it. When you’re Irish Catholic, you learn to do comedy at the foot of your brothers’ beds. It’s all about trying to make your family laugh. And I employ the same muscle today. It’s just that now I make a living out of it.”

O’Brien has moved from his beloved New York City home base to L.A. to host “The Tonight Show.”

But the red-headed, pale skin, freckle face funnyman, who has written for “The Simpsons” and “Saturday Night Live,” has by no means “gone Hollywood.”

“I can never go Hollywood. I'm genetically engineered to live in a bog in Northern Ireland," O’Brien has said. "I so clearly don't belong here. And you'll never see me in a trendy restaurant."

Poignantly, O’Brien will be Jay Leno’s final guest on “The Tonight Show” this Friday before beginning his new hosting stint on Monday.

NBC has announced that Irish-American blockbuster comedian and movie star Will Ferrell, who is promoting his new flick, “Land of the Lost,” will be O’Brien’s first guest. Seattle grunge rock band Pearl Jam, performing new songs from their upcoming album, will be his first musical guest.