Neil Simon, the prolific American playwright and Pulitzer Prize winner, died early Sunday morning in New York of complications stemming from pneumonia, according to his publicist. He was 91.

Simon began life in New York City on July 4, 1927. He wrote scores of classic plays, mostly Broadway comedies, including "The Odd Couple," "Sweet Charity," and "Lost in Yonkers," for which he won the 1991 Pulitzer Prize.

Simon was a critical darling, dubbed the "patron saint of laughter" by Time magazine.

"For almost half a century, his comedies have offered light at the end of whatever dark tunnel America has found itself in,” John Lahr of The New Yorker wrote in 2010.

He also won three Tony awards, including for "The Odd Couple" in 1965, and was nominated for the stage accolade 17 times, according to Broadway World. In addition, his work was honored with a Golden Globe and a Kennedy Center Honor.

"He was a giant of the American culture," Simon's longtime publicist Bill Evans said.

On Twitter, many remembered the writer as a craftsman of American lore, one that shaped the world of theater for the better.

"There is no American comedy writer whose work isn’t influenced by the rhythm and music of Neil Simon’s words. With gratitude, Doc," wrote Bill Prady, television writer and producer of shows like "The Big Bang Theory."

Actor Mark Hamill, star of the "Star Wars" series, tweeted calling Simon a "GIANT of the American Theater." Joshua Malina, who appeared in shows such as "The West Wing" and "Scandal," wrote that he'd always hoped to work with Simon one day.

Neil Simon - gone! A loss 4 the entire entertainment industry.

He could write a joke that would make you laugh, define the character, the situation, and even the world's problems. First time I met him he looked at me and said, "Where the hell did they find you?" What a gent. — Harvey Fierstein (@HarveyFierstein) August 26, 2018

"The final curtain has fallen for one of the gods of Broadway," The Tony Awards' official Twitter account wrote.

As a child, Marvin Neil Simon took solace from his parents' rocky marriage in the magic of film, particularly comedies, according to Biography.com.

He attended DeWitt Clinton High School in the Bronx, and then New York University, before enrolling in the U.S. Army Air Force Reserves. He studied at the University of Denver in Colorado until he was discharged from the Army in 1946, according to Biography.com.

Simon soon returned to New York and began working in the mailroom of Warner Brothers' Manhattan office. He eventually worked his way up and joined an all-star group of writers on the television series "Your Show of Shows," which included writing legends such as Mel Brooks, Larry Gelbart and Carl Reiner, in the early 1950s.

Throughout the 1960s and 1970s, Simon continued to churn out hits, which included "Sweet Charity," and "The Out-of-Towners." New York City was the canvas for the majority of his work.

"Perhaps the secret to Simon's success is his ability, brilliantly displayed in those four plays but evident from the very beginning, to show us — between, in, and around the funny lines — the pain, aspiration, and sheer panic behind all those unforgettable characters," the Kennedy Center wrote of Simon.

In "The Oxford Companion to American Theatre," Gerald Bordman wrote of Simon, "He is a shrewd observer of human foibles and a master of the one-line gag."

In 1975, Simon received a special Tony Award for his extraordinary contributions to the American Theater. He later received honorary degrees from Williams College and Hofstra University and was a Kennedy Center Honoree in 1995.

He is survived by daughters Ellen Simon, Nancy Simon, and Bryn Lander Simon, and wife Elaine Joyce Simon, whom he married in 1999.

CORRECTION (Aug. 26, 2018, 1:26 p.m. ET): An earlier version of this article misstated the day of Simon's death. He died early Sunday morning, not late Saturday night.