William Louis Petersen is an American actor and producer, best known for playing Dr. Gilbert "Gil" Grissom on the hit CBS series .

He has also portrayed President John F. Kennedy in the 1998 TV film The Rat Pack. Petersen is notoriously selective about the film roles he chooses, and has turned down roles in several films that went on to become modern classics.

Petersen, the youngest of six children, was born in Evanston, Illinois, to parents who worked in the furniture business. His father was Danish-American Arthur Edward Petersen, Sr. and his mother was German-American June Hoene Petersen. He has two brothers, Arthur, Jr. and Robert, plus three sisters: Anne, Mary Kay, and Elizabeth. He graduated from Bishop Kelly High School in Boise, Idaho, in 1972. He was accepted to Idaho State University on a football scholarship. While at Idaho State, Petersen took an acting course which changed the direction of his life. He left school along with his wife, Joanne, in 1974 and followed a drama professor to the Basque country where he studied as a Shakespearean actor. Petersen was interested in Basque culture and he studied the Basque language, Euskera, and gave his daughter the Basque name Maite Nerea ; she was born in Mondragón 1975. Petersen returned to Idaho intent on being an actor. Not wanting to work a non-acting job in Idaho, he returned to the Chicago area, living with relatives. He became active in the theater and earned his Actors' Equity card. He performed with the Steppenwolf Theatre Company, of which he has been an ensemble member since 2008, and was a co-founder of the Remains Theater Ensemble which also included other prominent Chicago actors Gary Cole and Ted Levine.

He is usually credited without his middle initial .

William Peterson was honored with the 2,379th star on the Hollywood Walk of Fame. Leron Gubler, President and CEO of the Hollywood Chamber of Commerce, presided over the ceremony. Guests included Marg Helgenberger, William Friedkin, David Berman, George Eads, Jorga Fox, Paul Guilfoyle, Robert David Hall, Eric Szmanda, Liz Vassey, and John Wellner.

6667 Hollywood Boulevard on February 3, 2009.

BIOGRAPHY

William Petersen was born in Evanston, Illinois, and first discovered acting while on a football scholarship at Idaho State University. He later studied acting in Spain.

Petersen, who has a distinguished background in film, theater and television, came to the attention of audiences worldwide when he took the role of Gil Grissom, the lead investigator on “CSI: Crime Scene Investigation” in 2000. Petersen received a Golden Globe Award nomination in 2003 for his role and while he departed from the series this past January 2009, he remains an executive producer.

His television credits include “Long Gone,” “The Rat Pack,” the Golden Globe Award winning mini-series “The Kennedys of Massachusetts” and “The Beast.”

His feature film credits include “To Live and Die in L.A.,” “Manhunter,” “Cousins,” “Young Guns II,” “Fear,” “The Contender” and the films “Hard Promises” and “Keep the Change,” both of which he also produced.

In 1979, he founded the Remains Theater Ensemble in Chicago with a group of fellow actors. In 1983, Petersen starred as Jack Henry Abbott in “In the Belly of the Beast” which he performed at the Wisdom Bridge Theatre in Chicago, at the Edinburgh Festival and at the Kennedy Center for the Performing Arts in Washington, DC.

In 1996 Petersen made his Broadway debut in a revival of Tennessee Williams’ “The Night of the Iguana.” He has appeared in a number of regional stage productions, including most recently “A Dublin Carol” at the Steppenwolf Theatre in Chicago, “A Streetcar Named Desire,” “The Time of Your Life,” “Glengarry Glen Ross,” “Fool for Love” and “Speed-the-Plow.” In the summer of 2009, Peterson stared in “Blackbird” on stage at the Victory Gardens Theatre in Chicago.

William Dieterle was a German actor and film director, who worked in Hollywood for much of his career.

He was born Wilhelm Dieterle, the youngest child of nine, to Jewish parents Jacob and Berthe Dieterle. As a child, he lived in considerable poverty and earned money by various means including carpentry and as a scrap dealer. He became interested in theater early and by the age of sixteen, he had joined a travelling theater company. His striking good looks and ambition soon paved the way as a leading romantic actor in theater productions. In 1919, he attracted the attention of Max Reinhardt in Berlin who hired him as an actor for his productions. He started acting in German films in 1921 to make more money and quickly became a popular character actor. He tired of acting quickly and wanted to direct.

He directed his first film in 1923, Der Mensch am Wege, which co-starred a young Marlene Dietrich, but he returned to acting for several years and appeared in such notable German films as Das Wachsfigurenkabinett and F.W. Murnau’s Faust. In 1927, Dieterle and his wife, Charlotte Hagenbruch, formed their own production company and returned to directing films, such as Sex in Chains in which he also played the lead role.

In 1930, Dieterle emigrated to the United States when he was offered a job in Hollywood to make German versions of American films; he became a citizen of the United States in 1937. He adapted quickly to Hollywood filmmaking and was soon directing original films. His first, The Last Flight, was a success and has been hailed as a forgotten masterpiece. Other films made during the 1930s include Jewel Robbery, Adorable, A Midsummer Night’s Dream with Reinhardt, The Story of Louis Pasteur, The Life of Emile Zola, Juarez and The Hunchback of Notre Dame, with Charles Laughton as Quasimodo.