Was nominated for Broadway's 2000 Tony Award as Best Actor (Play) for a revival of Sam Shepard's "True West."

Mother is from Lithuania. Father is Irish. He is the fifth of six children.

John is a wonderful singer who came out of a musical theater background - did all of his own singing in Chicago (2002).

In April 2004 he left the filming of Manderlay (2005) to be replaced by Slovenian actor Zeljko Ivanek. According to a report in Entertainment Weekly, he did so to protest against the killing of a donkey during production.

Originated the role of Marty in the 2002 musical "Marty" (book by Rupert Holmes, music by Charles Strouse, lyrics by Lee Adams), based on the 1955 movie Marty (1955).

Is a vegetarian.

Was member of the dramatic jury at the Sundance Film Festival in 2005.

In addition to having worked with Leonardo DiCaprio in The Aviator (2004), he has also worked with two other actors who played Howard Hughes: Jason Robards (from Melvin and Howard (1980)) in Magnolia (1999), and Tommy Lee Jones (from The Amazing Howard Hughes (1977) (TV)) in A Prairie Home Companion (2006).

Is a Chicago White Sox fan.

Lost a few pounds to play the rock star title character in Walk Hard: The Dewey Cox Story (2007).

Attended DePaul University in Chicago.

Director Antoine Fuqua wanted to cast him in his since aborted crime epic "Tru Blu" with Denzel Washington and Benicio Del Toro.

In 2003, he starred in three out of the five movies nominated for Best Picture. They are Chicago (2002), Gangs of New York (2002), and The Hours (2002).

Made a home video of himself singing in a bow tie and suit for director Rob Marshall who gave him his role in Chicago (2002).

For not only his broad, almost 6' 2" frame, curly hair, and everyman's mug, but also his straight-forward but thoughtful acting style, Reilly has frequently been dubbed "his generation's Gene Hackman".

Received a Bachelor of Fine Arts degree from DePaul University's Goodman School of Drama (Chicago) [1987]

Graduated from Brother Rice High School on the South Side of Chicago.