Ms. Stewart had a history of heart trouble and died at Beth Israel Hospital after a long illness, said Sam Rudy, a spokesman for La MaMa, where she had lived for many years in an apartment above the theater, on East Fourth Street.
Ms. Stewart was a dress designer when she started La MaMa in a basement apartment in 1961, a woman entirely without theater experience or even much interest in the theater. But within a few years, and with an indomitable personality, she had become a theater pioneer.
Not only did she introduce unusual new work to the stage, she also helped colonize a new territory for the theater, planting a flag in the name of low-budget experimental productions in the East Village of Manhattan and creating the capital of what became known as Off Off Broadway.
She was a vivid figure, often described as beautiful — an African-American woman whose long hair, frequently worn in cornrows, turned silver in her later years. Her wardrobe was flamboyant, replete with bangles, bracelets and scarves. Her voice was deep, carrying an accent reminiscent of her Louisiana roots.
Few producers could match her energy, perseverance and fortitude. In the decades after World War II her influence on American theater was comparable to that of Joseph Papp, founder of the New York Shakespeare Festival, though the two approached the stage from different wings. Papp straddled the commercial and noncommercial worlds, while Ms. Stewart’s terrain was international and decidedly noncommercial.
Her theater became a remarkable springboard for an impressive roster of promising playwrights, directors and actors who went on to accomplished careers both in mainstream entertainment and in push-the-envelope theater.
Al Pacino, Robert De Niro, Harvey Keitel, F. Murray Abraham, Olympia Dukakis, Richard Dreyfuss, Bette Midler, Diane Lane and Nick Nolte were among the actors who performed at La MaMa in its first two decades. Playwrights like Sam Shepard, Lanford Wilson, Harvey Fierstein, Maria Irene Fornes and Adrienne Kennedy developed early work there. So did composers like Elizabeth Swados, Philip Glass and Stephen Schwartz.
La MaMa directors included the visionary Robert Wilson; Tom O’Horgan (who helped create the rock musical “Hair” at the Public); Richard Foreman, who founded the imaginative Ontological Theater Company; Joseph Chaikin, who founded the Open Theater; and even Papp, before there was such a thing as the Public Theater. Meredith Monk, the composer, choreographer and director, presented her genre-bending pieces there regularly.
A few La MaMa plays, like the musical “Godspell,” moved to Broadway, and others had extended runs in commercial Off Broadway houses.
“Eighty percent of what is now considered the American theater originated at La MaMa,” Mr. Fierstein once said in an interview in Vanity Fair, perhaps exaggerating slightly. His play “Torch Song Trilogy” was developed there.
La MaMa became the quintessential theater on a shoestring. Salaries were minimal, ticket prices were low, and profits were nonexistent. For decades Ms. Stewart often swept the sidewalk in front of the theater herself.
But an adventurous theatergoer would be rewarded there. More than 3,000 productions of classic and postmodern drama, performance art, dance and chamber opera have been seen on La MaMa’s various stages. For Ms. Stewart a vast number of them were leaps of faith, arising from her instinct and belief that what artists need more than anything else is the freedom to create without interference. She would typically appear onstage before a performance, ring a cowbell and announce La MaMa’s dedication “to the playwright and all aspects of the theater.”
During the earliest days of her theater she supported her family of artists — her children, she called them — with the money she continued to earn designing clothes. She installed a washer and dryer in the basement for the performers, and many a visiting artist slept in her apartment or in the theaters themselves.
She didn’t begin directing shows herself until relatively late in her life. She often said she didn’t read plays; she read people. Her gifts, as affirmed by a MacArthur Foundation award in 1985, were intuitive and hard to pin down.
“If a script ‘beeps’ to me, I do it,” she said in an interview with The New York Times. “Audiences may hate these plays, but I believe in them. The only way I can explain my ‘beeps’ is that I’m no intellectual, but my instincts tell me automatically when a playwright has something.”
Her programming stretched far wider than the American theater. It was at La MaMa that Andrei Serban, a Romanian director transplanted to the United States, refought the Trojan War with his reinvention of Greek tragedy, “Fragments of a Greek Trilogy,” incorporating “Medea,” “The Trojan Women” and “Electra.” La MaMa became a magnet for the most adventurous European and American companies, including Peter Brook’s Paris group. Playing there now is “Being Harold Pinter,” a politically charged production by the Belarus Free Theater, based in Minsk, some of whose members were arrested and others forced underground by an authoritarian regime.
La MaMa’s range of activity was kaleidoscopic and multicultural, embracing an Eskimo “Antigone,” a Korean “Hamlet” and a splashy re-creation of the golden days of the Cotton Club in Harlem, directed by Ms. Stewart herself.
Mel Gussow, a theater critic and reporter for The Times who contributed to this obituary, died in 2005.
This article has been revised to reflect the following correction:
Correction: January 15, 2011
An obituary on Friday about Ellen Stewart, the founder of La MaMa Experimental Theater Club in New York, misidentified one of the writers whose works La MaMa presented. She is Adrienne Kennedy, not Adrienne Rich.
