Cassavetes was born in New York City to Greek immigrants. He grew up in Long Island and attended Colgate University before moving to the New York Academy of Dramatic Arts. On graduation in 1950, he continued acting in the theater. By 1953, he was doing small parts in films; he continued to play a James Dean-like "juvenile delinquent" throughout the 1950s. Cassavetes also acted on television, which was still finding its feet as a medium. His experience working within television's budgetary and schedule limits influenced his later film production style.
During this time he met and married actress Gena Rowlands, a fellow television actor. By 1956 Cassavetes had begun teaching method acting in workshops in New York City. An improvisation exercise in one workshop inspired the idea for his writing and directorial debut, Shadows (1960). Cassavetes raised the funds for production from friends and family, as well as listeners to a late-night radio talk show.
Film critic Leonard Malten calls Shadows "a watershed in the birth of American independent cinema". The movie was shot with a 16mm handheld camera on the streets of New York. Much of the dialogue was improvised, and the crew were class members or volunteers. The jazz score, by legend Charles Mingus, underlines the movie's Beat Generation theme of alienation and raw emotion. The movie's plot focuses on an interracial relationship — still a taboo subject in Eisenhower-era America.
Cassavetes was unable to get American distributors to carry Shadows, so he took it to Europe, where it won the Critics Award at the Venice Film Festival. European distributors later released the movie in the United States as an import.
Although the viewership of Shadows in the United States was slight, it did gain attention from the Hollywood studios. Cassavetes directed two movies for Hollywood in the early 1960s — Too Late Blues and A Pair of Boots — but the experience was exasperating. The intervention of the studios, the lack of creative control, and the over-all dumbing down of his work was unbearable. Cassavetes refused to go through the process again.
His strategy, brought on by necessity, was to work as an actor in mainstream movies, and channel the funds he made there into his work as a director. He didn't just clockwatch as an actor, though; he did masterly work in blockbuster hits of the late 1960s, including World War II epic The Dirty Dozen (1967) — for which he was nominated for an Academy Award for Best Supporting Actor — and Roman Polanski's Rosemary's Baby (1968).
His next independent film was Faces, which lay down new themes for later work. Starring Cassavetes's wife Rowlands, Faces depicted a contemporary suburban marriage in the process of slow disintegration, with the accompanying desperate and degrading sexual improprieties. Cassavetes held an unflinching camera on the pettiness and emotional greed of the distancing husband and wife and their lovers, but in the end the pathos of their story gives them a unexpected dignity. Faces was a critical and financial success, nominated for two Academy Awards (Best Supporting Actor and Actress).
After Faces Cassavetes could concentrate more fully on his directorial work. He had enough leverage at this point that he could make movies in the studio system, yet retain full creative control. Husbands (1970) starred Cassavetes himself, with Peter Falk and Ben Gazzara. They play a trio of men escaping their marriages for minor peccadillos. Another in the 1970s include Minnie and Moskovitz, about a misdirected young woman seeking love, and starring Rowlands again with a small part for Cassavetes's mother, Katherine.
His two masterpieces of the 1970s, however, were made independently. A Woman Under the Influence (1974) stars Rowlands as an increasingly eccentric housewife trying to keep her hold on reality. Peter Falk played her husband, who tries to keep up a facade of normality, but ultimately makes the difficult decision of committing her to a mental institution. The characters were nuanced, and the ethical situations were measured in shades of gray. The wife's behavior, while disturbing and disconcerting for those around her, is not obviously dangerous or unstable. Rowlands is an expert collaborator in the story, playing Mabel with subtlety and energy; she received an Academy Award nomination for Best Actress, while Cassavetes was nominated for Best Director.
The Killing of a Chinese Bookie (1976) was a movie about the experience of men as much as Influence was about women. Ben Gazzara plays Cosmo Vitelli, a small-time strip-club owner with an out-of-control gambling habit, who is convinced by mobsters to commit a murder to pay off his debt. Driven by fear and uncertainty, Vitelli deceives friend and foe alike. Author Christos Tsiolkas said of Bookie that it showed "being a man means knowing gutlessness better than knowing courage, that failure stays with you long after success."
Cassavetes continued to work through the 1980s, although personal troubles with alcohol were beginning to take their toll. Gloria (1980) is a more conventional thriller starring Rowlands as a mob moll who runs off with a young boy orphaned by the mob and soon to be next. Love Streams (1984) starred Cassavetes as an aging lothario who suffers the overbearing affection of his recently divorced sister. Sadly, Cassavetes's last movie, Big Trouble (1986), was a last-minute project picked up as a favor when a younger director friend peremptorily quit the project. The movie, racked by incompatible studio and director edits, was, in Cassavetes's words, "a disaster". Already ill, he was heartbroken that it would be the last film he would do.
Cassavetes's personality was overpowering and driven. He lived to make film, and sacrificed his colleagues and himself to the process. The intense effort took its toll; an alcoholic, he died of cirrhosis of the liver in 1989. He was survived by Rowlands, who continued to act, and three children. His son, Nick Cassavetes, followed in his father's footsteps, and made 1997's She's So Lovely from the elder Cassavetes's screenplay.