See Marx brothers (fencing) for the 16th century German brotherhood.

The Marx Brothers' stage shows became popular just as Hollywood was making the change to "talkies". They struck a contract with Paramount and embarked on their career in films. Their first two released films (they had previously made – but not released – one short silent film titled Humor Risk) were adaptations of Broadway shows: The Cocoanuts (1929) and Animal Crackers (1930). Both were written by George S. Kaufman and Morrie Ryskind. Following these two feature-length films, they made a short film that was included in Paramount's twentieth anniversary documentary, The House That Shadows Built (1931), in which they adapted a scene from I'll Say She Is. Their third feature-length film, Monkey Business (1931), was their first that was not based on a stage production. Horse Feathers (1932), in which the brothers satirized the American College system and Prohibition, was their most popular film yet, and won them the cover of Time magazine. It included a running gag from their films where Harpo revealed having nearly everything in his coat. At various points in Horse Feathers Harpo pulls out of his coat: a wooden mallet, a fish, a coiled rope, a tie, a poster of a woman in her underwear, a cup of hot coffee, a sword, and a candle burning at both ends.

Their last Paramount film, Duck Soup (1933) – directed by the most highly regarded director they ever worked with, Leo McCarey – is now considered by many their finest: it is the only Marx Brothers film on the American Film Institute's "100 years ... 100 Movies" list. Common wisdom holds that the film failed, but this was actually incorrect. It did not do as well as Horse Feathers, but was the sixth highest-grosser of 1933. The Marx Brothers left Paramount because of disagreements over creative decisions and financial issues.

Tired of the unrewarding status of playing second (or fourth)-banana to his elder brothers, Zeppo left the act to become an agent. He remained his brothers' agent for the remainder of their career as the Marx Bros. Groucho and Chico did radio, and there was talk of returning to Broadway. At a bridge game with Chico, Irving Thalberg began discussing the possibility of the Marxes coming to Metro-Goldwyn-Mayer, and they signed, now known as "The Three Marx Brothers," or simply "The Marx Bros." Thalberg insisted on a strong story structure, unlike the free-for-all scripts at Paramount. In the rest of their films, their comedy would be interwoven with romantic plots and non-comic musical numbers while the targets of their mischief was largely confined to clear villains. Only their Paramount films represent what is considered their genius in its pure form.

The first film that the brothers shot with Thalberg was A Night at the Opera (1935), a satire on the world of opera music, where the brothers help two young singers in love by throwing a production of Il Trovatore into chaos. The film was a great success, and for decades (until critics and fans took a second look at their Paramount films) was generally considered their best work. The film was a huge success, followed two years later by the even bigger hit A Day at the Races (1937), where the brothers caused mayhem in a sanitarium and at a horse race. However, during shooting in 1936, Thalberg died suddenly, and without him, the brothers didn't have an advocate at MGM.


After a short experience at RKO (Room Service, 1938), the Marx Brothers made three more films before leaving MGM, At the Circus (1939), Go West (1940), and The Big Store (1941). Prior to the release of "The Big Store" the team announced their retirement from the screen, but Chico was in dire financial straits and to help settle his gambling debts, the Marx Brothers made another two films together, A Night in Casablanca (1946) and Love Happy (1949), both of them released by United Artists.

Groucho and Chico appeared together briefly in a short 1957 film promoting the Saturday Evening Post entitled "Showdown at Ulcer Gulch," directed by animator Shamus Culhane, Chico's son-in-law. Then they worked together, but in different scenes, in The Story of Mankind (1957). In 1959, all three acted in a TV pilot, Deputy Seraph, to star Harpo and Chico as blundering angels; Groucho would appear in every third episode as their boss, the "Deputy Seraph" (A seraph is an angel). The pilot was never finished when it was discovered that Chico was seriously ill with arteriosclerosis and was uninsurable. He and Harpo did appear together in a half-hour film shot later that year,The Incredible Jewel Robbery, a pantomime show with the pair as would-be jewel thieves. Groucho made a brief appearance in the last scene.

From the 1940s onward, Chico and Harpo made nightclub and casino appearances, sometimes together. Groucho began a career as a radio and television entertainer. From 1947 to the early-1960s he was the host of the humorous quiz show You Bet Your Life. He was also an author; his writings include the autobiographical Groucho and Me (1959) and Memoirs of a Mangy Lover (1964).

The 1957 television talk show Tonight! America After Dark, hosted by Jack Lescoulie, may supply the only public footage in which all five brothers appeared.

In 1970, the Four Marx Brothers had a brief reunion of sorts in the animated ABC television special The Mad, Mad, Mad Comedians, produced by Rankin-Bass animation (of Rudolph the Red-Nosed Reindeer fame). The special featured animated reworkings of various famous comedians' acts, including W.C. Fields, Jack Benny, George Burns, Henny Youngman, The Smothers Brothers, Flip Wilson, Phyllis Diller, Jack E. Leonard, George Jessel, and the Marx Brothers. Most of the comedians provided their own voices for their animated counterparts, except for W.C. Fields, Chico Marx (who had died), and Zeppo Marx (who left show business in 1933). Voice actor Paul Frees filled in for all three. The Marx Brothers' segment was a reworking of a scene from their Broadway play I'll Say She Is, a parody of Napoleon which Groucho considered among the Brothers' funniest routines. The sketch featured animated representations, if not the voices, of all four brothers. Romeo Muller is credited as having written special material for the show, but the script for the classic "Napoleon Scene" was probably supplied by Groucho.

On January 16 1977, The Marx Brothers were inducted into the Motion Picture Hall of Fame.

Many TV shows and movies have used Marx Brothers references; such as multiple episodes of Disney's The Suite Life of Zack and Cody have similar jokes, too close to be coincidence. Animaniacs and Tiny Toons have also featured Marx Brothers jokes and skits.