Viewed as a master of situation comedy and one-liners, Mr. Gelbart won Tonys for Best Book of a Musical for City of Angels, which he was recently adapting as a screen musical, and A Funny Thing Happened on the Way to the Forum, which he co-wrote with Burt Shevelove.
His wife, Pat, told the Los Angeles Times that Mr. Gelbart, who was battling cancer, died at his home in Beverly Hills, CA.
Mr. Gelbart developed the Robert Altman movie "M*A*S*H" into the hit TV series, co-wrote the screenplay to the Hollywood comedy "Tootsie," and wrote the Broadway plays Sly Fox (based on Ben Jonson's Volpone) and Mastergate. He was recently working with lyricist David Zippel on new musicals.
Northlight Theatre in Skokie, IL, had a spring 2008 sold-out hit with the world premiere of Better Late, a late-career comedy that Mr. Gelbart co-wrote with Craig Wright. John Mahoney and Mike Nussbaum starred in the tale, the premise of which seems pure Gelbart: Billed as a "bitingly funny December-December-December romance," it concerned reluctant roommates Julian (played by Nussbaum), who is forced to move in with his ex-wife and her new husband (Mahoney) in order to recuperate from a sudden illness. Comedy, as they used to say in pitch meetings, ensued. Northlight artistic director B.J. Jones billed Mr. Gelbart this way on Sept. 11: "One of the quickest comic minds I've ever known and one of the fiercest and most compassionate liberals." Jones told Playbill.com, "Comedy has lost a legend. I am so privileged to have worked with him on his last and most personal play."
Quips and one-liners came easy to Mr. Gelbart. He began his career in radio and came of age in the smoky writers' rooms of TV comedy shows of the 1950s: variety shows featuring Bob Hope, Red Buttons and Sid Caesar. The writing staff of "Caesar's Hour" included Neil Simon, Carl Reiner and Mel Brooks, who, like Mr. Gelbart, would become American comedy legends.
Mr. Gelbart shared three Emmy nominations for comedy writing for "Caesar's Hour."
His first brush with Broadway was with the bomb The Conquering Hero, based on the film "Hail, the Conquering Hero." His Forum, however, was packed with broad vaudeville jokes and situations (drawing on ancient Roman comedy), and the show was a smash. It helped that the cast was filled with clowns like Zero Mostel and Jack Gilford.
His 1976 Jonson-inspired low comedy, Sly Fox, starring George C. Scott was revived on Broadway in 2004 (with Richard Dreyfuss). Mr. Gelbart moved the plot (about a greedy miser who seeks the fortunes of all around him) from Renaissance Venice to Gold Rush San Francisco.
A multiple Academy Award nominee, Mr. Gelbart wrote or co-wrote screenplays for the films "Neighbors," "The Notorious Landlady," "The Wrong Box," "Not With My Wife, You Don't!," "Movie Movie," "Blame It on Rio," "Oh, God" (Oscar nomination), "Tootsie" (sharing a screenwriting Oscar nomination with Murray Schisgal and Don McGuire), and the HBO movies "Barbarians at the Gate," "Weapons of Mass Destruction" and "And Starring Pancho Villa as Himself."
He wrote the pilot for the TV series "M*A*S*H," one of the most successful, acclaimed and beloved American TV series of all time. He was a co-executive producer of the series and won Emmys for his work on it. It ran 11 years, but Mr. Gelbart moved on after four.
Mr. Gelbart was the son of Eastern European immigrants, the L.A. Times reported. His father, a barber, was from Latvia, and his seamstress mother was from Poland. Mr. Gelbart was born in Chicago and spoke only Yiddish until he was four. He and his family moved to Los Angeles when he was a teenager. He got his funnybone from his mother, who "was extremely witty and caustic," he told People magazine.
Mr. Gelbart wrote a 1998 memoir, "Laughing Matters."
According to the L.A. Times, one of Mr. Gelbart's father's Hollywood customers was comedian Danny Thomas, who was heard on the radio show "Maxwell House Coffee Time." Mr. Gelbart's father pitched Thomas on the comic gifts of the 16-year-old Larry, and Thomas asked for a sample. "My only real gift," Mr. Gelbart would later write, "was for showing off, doing imitations, putting together sketches, speeches, monologues at Fairfax High School," but he supplied a sample to Thomas and snagged a writing job. By age 18, he was a staff writer on radio's "Duffy's Tavern."
He was soon drafted into the military and assigned to Armed Forces Radio Service.
Mr. Gelbart continued writing until three weeks ago, his wife told the L.A. Times on Sept. 11.
Mr. Gelbart married Broadway actress and singer Patricia Marshall in 1956. In addition to his wife and their two children, Adam and Becky, Mr. Gelbart is survived by his stepchildren, Gary and Paul Markowitz; six grandchildren and two great-grandchildren.