Gary Alan Sinise was born in Blue Island, Illinois, to Mylles S. Alsip and Robert L. Sinise, a film editor, who had a profound impact on his life. He is of Italian descent from his paternal grandfather, as well as English, Scottish, Irish, French, German, and Swedish ancestry. His family relocated to Highland Park, Illinois, where he attended high school, often finding himself in trouble, playing in bands, and neglecting his studies.
Gary's love for acting was ignited when he and his friends tried out for the production of "West Side Story" as a lark, but he became hooked on acting after the show's closing night. He credits his drama teacher, Barbara Patterson, for nurturing his passion for theatre. In 1974, Gary, along with his friends Terry Kinney and Jeff Perry, co-founded the Steppenwolf Theatre Company in Chicago, initially performing in a church basement but gradually growing in stature and recognition in the Chicago area.
Gary not only acted in numerous plays but also directed some of Steppenwolf's most notable productions, including Sam Shepard's "True West". The company made its off-Broadway debut with that production, starring Gary and John Malkovich, and its Broadway debut with "The Grapes of Wrath" at the Cort Theatre in 1990. Gary's Hollywood career also began as a director, working on two episodes of the TV series "Crime Story" in 1986, followed by the feature film "Miles from Home" in 1988, starring Richard Gere.
Gary's first feature film as an actor was the World War II fable "A Midnight Clear" in 1992, the same year he combined his acting and directing talents with the critically acclaimed "Of Mice and Men". However, it was his performance in the miniseries "The Stand" in 1994 that brought him widespread recognition. He then starred in the blockbuster film "Forrest Gump" as "Lt. Dan", earning him numerous awards and an Oscar nomination.
Gary's portrayal of the disabled, emotionally tortured veteran in "Forrest Gump" earned him critical acclaim and numerous awards, including the Golden Globe and Screen Actors Guild Awards, as well as an Emmy nomination. In 1995, he reunited with Tom Hanks in "Apollo 13" and starred in the HBO film "Truman", which earned him the Golden Globe and Screen Actors Guild Awards and an Emmy nomination.
Gary is married to Moira Sinise, an actress and original member of the Steppenwolf company, and they have three children, Sophie Sinise, McCanna Anthony Sinise, and Ella Sinise.