At the age of three, Keaton began performing with his parents in The Three Keatons. He first appeared on stage in 1899 in Wilmington, Delaware. The act was mainly a comedy sketch. Myra played the saxophone to one side, while Joe and Buster performed on center stage. The young Keaton would goad his father by disobeying him, and the elder Keaton would respond by throwing him against the scenery, into the orchestra pit, or even into the audience. A suitcase handle was sewn into Keaton’s clothing to aid with the constant tossing. The act evolved as Keaton learned to take trick falls safely; he was rarely injured or bruised on stage. This knockabout style of comedy led to accusations of child abuse, and occasionally, arrest. However, Buster Keaton was always able to show the authorities that he had no bruises or broken bones. He was eventually billed as “The Little Boy Who Can’t Be Damaged”, with the overall act being advertised as “The Roughest Act That Was Ever in the History of the Stage”. Decades later, Keaton said that he was never hurt by his father and that the falls and physical comedy were a matter of proper technical execution. In 1914, Keaton told the Detroit News: “The secret is in landing limp and breaking the fall with a foot or a hand. It’s a knack. I started so young that landing right is second nature with me. Several times I’d have been killed if I hadn’t been able to land like a cat. Imitators of our act don’t last long, because they can’t stand the treatment.”

In February 1917, Keaton met Roscoe “Fatty” Arbuckle at the Talmadge Studios in New York City, where Arbuckle was under contract to Joseph M. Schenck. Joe Keaton disapproved of films, and Buster also had reservations about the medium. During his first meeting with Arbuckle, he was asked to jump in and start acting. Buster was such a natural when making his first film The Butcher Boy he was hired on the spot. At the end of the day’s work, he asked to borrow one of the cameras to get a feel for how it worked. He took the camera back to his hotel room where he dismantled and reassembled it by morning. Keaton later claimed that he was soon Arbuckle’s second director and his entire gag department. He appeared in a total of 14 Arbuckle shorts, running into 1920. They were popular, and contrary to Keaton’s later reputation as “The Great Stone Face”, he often smiled and even laughed in them. Keaton and Arbuckle became close friends, and Keaton was one of few people, along with Charlie Chaplin, to defend Arbuckle’s character during accusations that he was responsible for the death of actress Virginia Rappe. (Arbuckle was eventually acquitted, with an apology from the jury for the ordeal he had undergone. )

In 1920, The Saphead was released, in which Keaton had his first starring role in a full-length feature. It was based on a successful play, The New Henrietta, which had already been filmed once, under the title The Lamb, with Douglas Fairbanks playing the lead. Fairbanks recommended Keaton to take the role for the remake five years later, since the film was to have a comic slant.

On May 31, 1921, Keaton married Natalie Talmadge, sister of actresses Norma Talmadge and Constance Talmadge. She co-starred with him in Our Hospitality. The couple had sons Joseph, called James (June 2, 1922 – February 14, 2007), and Robert (February 3, 1924 – July 19, 2009), both of whom later took the surname Talmadge.

The International Buster Keaton Society was founded on October 4, 1992: Keaton’s birthday. Dedicated to bringing greater public attention to Keaton’s life and work, the membership includes many individuals from the television and film industry: actors, producers, authors, artists, graphic novelists, musicians, and designers, as well as those who simply admire the magic of Buster Keaton. The Society’s nickname, the “Damfinos,” draws its name from a boat in Keaton’s 1921 comedy, The Boat.

Keaton also appeared in a comedy routine about two inept stage musicians in Charlie Chaplin’s Limelight (released in 1952), recalling the vaudeville of The Playhouse. With the exception of Seeing Stars, a minor publicity film produced in 1922, Limelight was the only time in which the two would ever appear together on film.

In his essay Film-arte, film-antiartístico, artist Salvador Dalí declared the works of Keaton to be prime examples of “anti-artistic” filmmaking, calling them “pure poetry”. In 1925, Dalí produced a collage titled The Marriage of Buster Keaton featuring an image of the comedian in a seated pose, staring straight ahead with his trademark boater hat resting in his lap.

With the failure of his marriage and the loss of his independence as a film-maker, Keaton lapsed into a period of alcoholism. In 1926, he spent $300,000 to build a 10,000-square-foot (930 m) home in Beverly Hills designed by architect Gene Verge Sr., which was later owned by James Mason and Cary Grant.

Keaton signed with Metro-Goldwyn-Mayer in 1928, a business decision that he would later call the worst of his life. He realized too late that the studio system MGM represented would severely limit his creative input. For instance, the studio refused his request to make his early project, Spite Marriage, as a sound film and after the studio converted, he was obliged to adhere to dialogue-laden scripts. However, MGM did allow Keaton some creative participation on his last originally developed/written silent film The Cameraman, 1928, which was his first project under contract with them, but hired Edward Sedgwick as the official director.

After the birth of Robert, the relationship began to suffer. Talmadge decided not to have more children, and this led to the couple staying in separate bedrooms. Her financial extravagance was another factor in the breakdown of the marriage, as she would spend up to a third of his salary on clothes. Keaton dated actress Dorothy Sebastian beginning in the 1920s and Kathleen Key in the early 1930s. After attempts at reconciliation, Talmadge divorced him in 1932, taking his entire fortune and refusing to allow any contact between him and his sons. Keaton was reunited with them about a decade later when his older son turned 18.

Keaton was briefly institutionalized, according to the Turner Classic Movies documentary So Funny it Hurt. He escaped a straitjacket with tricks learned from Harry Houdini. In 1933, he married his nurse Mae Scriven during an alcoholic binge about which he afterwards claimed to remember nothing. Scriven claimed that she didn’t know Keaton’s real first name until after the marriage. She filed for divorce in 1935 after finding Keaton with Leah Clampitt Sewell, the wife of millionaire Barton Sewell, in a hotel in Santa Barbara. They divorced in 1936 at great financial cost to Keaton.

Keaton was so demoralized during the production of 1933’s What! No Beer? that MGM fired him after the filming was complete, despite the film being a resounding hit. In 1934, Keaton accepted an offer to make an independent film in Paris, Le Roi des Champs-Élysées. During this period, he made another film, in England, The Invader (released in the United States as An Old Spanish Custom in 1936).

Upon Keaton’s return to Hollywood in 1934, he made a screen comeback in two-reel comedies for Educational Pictures. Most of these 16 films are simple visual comedies, with many of the gags supplied by Keaton himself, often recycling ideas from his family vaudeville act and his earlier films. The high point in the Educational series is Grand Slam Opera (1936), featuring Buster in his own screenplay as an amateur-hour contestant.

When the Educational series lapsed in 1937, Keaton returned to MGM as a gag writer, supplying material for the final three Marx Brothers MGM films At the Circus (1939), Go West (1940), and The Big Store (1941); these were not as artistically successful as the Marxes’ previous MGM features.

In 1939, Columbia Pictures hired Keaton to star in 10 two-reel comedies; the series ran for two years, and comprise his last series as a starring comedian. The director was usually Jules White, whose emphasis on slapstick and farce made most of these films resemble White’s famous Three Stooges shorts. Keaton’s personal favorite was the series’s debut, Pest from the West, a shorter, tighter remake of Keaton’s little-viewed 1934 feature The Invader; it was directed not by White but by Del Lord, a veteran director for Mack Sennett. Moviegoers and exhibitors welcomed Keaton’s Columbia comedies, proving that the comedian had not lost his appeal. However, director White’s insistence on blunt, violent gags resulted in the Columbia shorts being the least inventive comedies he made. The final entry was She’s Oil Mine (1941), a two-reel reworking of Keaton’s 1932 feature The Passionate Plumber. Columbia and White wanted to sign Keaton for more shorts but the comedian declined, resolving that he would never again “make another crummy two-reeler.”

On May 29, 1940, Keaton married Eleanor Norris (July 29, 1918 – October 19, 1998), who was 23 years his junior. She has been credited with saving his life by stopping his heavy drinking and helping to salvage his career. The marriage lasted until his death. Between 1947 and 1954, they appeared regularly in the Cirque Medrano in Paris as a double act. She came to know his routines so well that she often participated in them on television revivals.

Critics rediscovered Keaton in 1949 and producers occasionally hired him for bigger “prestige” pictures. He had cameos in such films as In the Good Old Summertime (1949), Sunset Boulevard (1950), and Around the World in 80 Days (1956). In In the Good Old Summertime, Keaton personally directed the stars Judy Garland and Van Johnson in their first scene together, where they bump into each other on the street. Keaton invented comedy bits where Johnson keeps trying to apologize to a seething Garland, but winds up messing up her hairdo and tearing her dress.

In 1949, comedian Ed Wynn invited Keaton to appear on his CBS Television comedy-variety show, The Ed Wynn Show, which was televised live on the West Coast. Kinescopes were made for distribution of the programs to other parts of the country, since there was no transcontinental coaxial cable until September 1951. Reaction was strong enough for a local Los Angeles station to offer Keaton his own show, also broadcast live, in 1950.

In 1954, Buster and Eleanor Keaton met film programmer Raymond Rohauer, with whom they developed a business partnership to re-release his films. Actor James Mason had bought the Keatons’ house and found numerous cans of films, among which was Keaton’s long-lost classic The Boat. Keaton had prints of the features Three Ages, Sherlock Jr., Steamboat Bill, Jr., and College (missing one reel), and the shorts “The Boat” and “My Wife’s Relations”, which Keaton and Rohauer then transferred to Cellulose acetate film from deteriorating nitrate film stock.

On April 3, 1957, Keaton was surprised by Ralph Edwards for the weekly NBC program This Is Your Life. The program also promoted the release of the biographical film The Buster Keaton Story with Donald O’Connor. In December 1958, Keaton was a guest star in the episode “A Very Merry Christmas” of The Donna Reed Show on ABC. He returned to the program in 1965 in the episode “Now You See It, Now You Don’t”. In August 1960, Keaton played mute King Sextimus the Silent in the national touring company of the Broadway musical Once Upon A Mattress. In 1960, he returned to MGM for the final time, playing a lion tamer in a 1960 adaptation of Mark Twain’s The Adventures of Huckleberry Finn. Much of the film was shot on location on the Sacramento River, which doubled for the Mississippi River setting of Twain’s book. In 1961, he starred in The Twilight Zone episode “Once Upon a Time”, which included both silent and sound sequences. He worked with comedian Ernie Kovacs on a television pilot tentatively titled “Medicine Man,” shooting scenes for it on January 12, 1962—the day before Kovacs died in a car crash. “Medicine Man” was completed but not aired.

A 1957 film biography, The Buster Keaton Story, starring Donald O’Connor as Keaton was released. The screenplay, by Sidney Sheldon, who also directed the film, was loosely based on Keaton’s life but contained many factual errors and merged his three wives into one character. A 1987 documentary, Buster Keaton: A Hard Act to Follow, directed by Kevin Brownlow and David Gill, won two Emmy Awards.

Keaton was presented with a 1959 Academy Honorary Award at the 32nd Academy Awards, held in April 1960. Keaton has two stars on the Hollywood Walk of Fame: 6619 Hollywood Boulevard (for motion pictures); and 6225 Hollywood Boulevard (for television).

Keaton also found steady work as an actor in TV commercials, including a series of silent ads for Simon Pure Beer made in 1962 by Jim Mohr in Buffalo, New York, in which he revisited some of the gags from his silent film days.

Keaton designed and modified his own pork pie hats during his career. In 1964, he told an interviewer that in making “this particular pork pie”, he “started with a good Stetson and cut it down”, stiffening the brim with sugar water. The hats were often destroyed during Keaton’s wild film antics; some were given away as gifts and some were snatched by souvenir hunters. Keaton said he was lucky if he used only six hats in making a film. Keaton estimated that he and his wife Eleanor made thousands of the hats during his career. Keaton observed that during his silent period, such a hat cost him around two dollars (~$25-30 in 2018 dollars); at the time of his interview, he said, they cost almost $13 (~$105 in 2018 dollars).

In 1965, Keaton starred in the short film The Railrodder for the National Film Board of Canada. He traveled from one end of Canada to the other on a motorized handcar, wearing his traditional pork pie hat and performing gags similar to those in films that he made 50 years before. The film is also notable for being his last silent screen performance. He played the central role in Samuel Beckett’s Film (1965), directed by Alan Schneider. Also in 1965, he traveled to Italy to play a role in Due Marines e un Generale, co-starring Franco Franchi and Ciccio Ingrassia.

In 1965 he appeared on the CBS television special A Salute to Stan Laurel, a tribute to the comedian and friend of Keaton who had died earlier that year.

Buster Keaton’s last commercial film appearance was in A Funny Thing Happened on the Way to the Forum (1966), which was filmed in Spain in September–November 1965. He amazed the cast and crew by doing many of his own stunts, although Thames Television said that his increasingly ill health did force the use of a stunt double for some scenes. His final appearance on film was a 1965 safety film produced in Toronto by the Construction Safety Associations of Ontario, and he died shortly after completing it.

Keaton died of lung cancer on February 1, 1966, aged 70, in Woodland Hills, California. Despite being diagnosed with cancer in January 1966, he was never told he was terminally ill. Keaton thought that he was recovering from a severe case of bronchitis. Confined to a hospital during his final days, Keaton was restless and paced the room endlessly, desiring to return home. In a British television documentary about his career, his widow Eleanor told producers from Thames Television that Keaton was up out of bed and moving around, and even played cards with friends who came to visit the day before he died. He was buried at Forest Lawn Memorial Park Cemetery in Hollywood Hills, California.

In 1994, caricaturist Al Hirschfeld penned a series of silent film stars for the United States Post Office, including Rudolph Valentino and Keaton. Hirschfeld said that modern film stars were more difficult to depict, that silent film comedians such as Laurel and Hardy and Keaton “looked like their caricatures”.

In 2012, Kino Lorber released The Ultimate Buster Keaton Collection, a 14-disc Blu-ray box set of Keaton’s work, including 11 of his feature films.

Meanwhile, Keaton’s big-screen career continued. He had a cameo as Jimmy, appearing near the end of the film It’s a Mad, Mad, Mad, Mad World (1963). Jimmy assists Spencer Tracy’s character, Captain C. G. Culpepper, by readying Culpepper’s ultimately-unused boat for his abortive escape. (The restored version of that film, released in 2013, contains a scene where Jimmy and Culpeper talk on the telephone. Lost after the comedy epic’s “roadshow” exhibition, the audio of that scene was discovered, and combined with still pictures to recreate the scene.)

On June 16, 2018, the International Buster Keaton Society laid a four-foot plaque in honor of both Keaton and Charles Chaplin on the corner of the shared block (1021 Lillian Ave) where each had made many of their silent comedies in Hollywood. In honor of the event, the City of Los Angeles declared the date “Buster Keaton Day.”

In 2018 filmmaker Peter Bogdanovich released The Great Buster, a documentary about Keaton’s life, career, and legacy.