; the deal was later extended three extra years
Disney also developed the idea of lifelike realism in animation to a degree that has rarely been surpassed since his time. Continuing emphasis on story development and characterization resulted in yet another smash hit for Disney: Three Little Pigs (1933), which is seen as the first cartoon in which multiple characters displayed unique, individual personalities; the cartoon is still considered to be the most successful animated short of all time
, and also featured the hit song that became the anthem in fighting the Great Depression "Who's Afraid of the Big Bad Wolf"
In 1937, Disney was the first to use advanced multi-plane camera shots in his Silly Symphony cartoon The Old Mill
Much of Disney's work was heavily influenced by European stories and myths, and the work of illustrators such as Doré and Busch. By 1934, Mickey was also making 600,000.00 a year in merchandise and cartoons 
Disney had competitors, though none were able to topple his studio from the throne of animation until the 1940s. Disney's greatest competitor during the silent era, the Pat Sullivan studio, faced its downfall after an uninspired attempt at bringing Felix the Cat into the sound medium; Sullivan put sound into Felix cartoons that had already been drawn
Without another star power competitor for Mickey, this downfall was a big break for Disney, as Mickey's popularity would afterwards skyrocket throughout the early 1930s
In addition, Disney was able to make Mickey more appealing among theater audiences by colorizing and partially redesigning him in 1935
Mickey was later redesigned again when the production of the Sorcerer's Apprentice segment for Fantasia began in 1938, and was regarded as Mickey's most appealing design
At first, Mickey was drawn by Disney's long-time partner and friend Ub Iwerks, who was also a technical innovator in cartoons, and drew an average of 600 drawings for Disney on a daily basis
; Disney was responsible for the ideas in the cartoons, and Iwerks was responsible for bringing them to life
However, Iwerks left the Disney studio in 1930 to form his own company, which was financially backed by Celebrity Pictures owner Pat Powers
After his departure, Disney eventually found a number of different animators to replace Iwerks. Iwerks would produce three cartoon series during the 1930s: Flip the Frog and Willie Whopper for Metro-Goldwyn-Mayer, and the ComiColor Cartoons for Pat Powers' Celebrity Productions. However, none of these cartoons could come close to matching the success of Disney or Fleischer cartoons, and in 1933, MGM-Iwerks' cartoon distributor since 1930 ended distribution of his cartoons in favor of distributing Harman and Ising cartoons, and Iwerks left after his contract expired in 1934
After his stay with MGM, Iwerks' cartoons were distributed by Celebrity Pictures, and Iwerks would answer to Disney's use of Technicolor and create the Comicolor series, which aired cartoons in two-strip Cinecolor
However, by 1936, the Iwerks Studio would lose a lot of money and would close after Pat Powers withdrew financial aid to the studio
However, during the early 1930s, stricter censorship rules enforced by the new Production Code in 1934 required animation producers to remove bathroom gags and risqué humor. The Fleischers in particular had to tone down the content of their Betty Boop cartoons, which waned in popularity afterwards
The Fleischers also had produced a number of Color Classics cartoons during the mid- and late-1930s- which attempted to emulate Walt Disney's use of color-, but the series was not a success
Despite all this, the Popeye series remained strong.
After disputes over money, Harman-Ising parted company with Schlesinger in 1933 -taking Bosko with them-, and began producing Happy Harmonies cartoons for MGM after that studios contract with Ub Iwerks had run its course in 1934. The Happy Harmonies shorts were also emulative of Disney's works, in particular the Disney Silly Symphonies cartoons, and were in Technicolor as well
At Warner Bros., Schlesinger began his own cartoon operation, hiring Harman-Ising animator Friz Freleng and several others to run the studio. Schlesinger also answered to Disney's use of color in Silly Symphonies cartoons in 1934, and began making all future Merrie Melodies cartoons in color
In 1935, Schlesinger hired a new animation director who proceeded to revitalize the studio: Tex Avery. Avery brought a wacky style of animation to the studio that would increase the Warner Bros. cartoons' popularity in the crowded marketplace. With Avery's influence, Schlesinger's staff would give birth to a new crowd of popular animated cartoons stars: Porky Pig, Daffy Duck, Bugs Bunny, and many others. Under Avery, Porky Pig would become the first Warner Bros. character to achieve star power, and follow-up characters Daffy Duck and Bugs Bunny would also achieve star power
Meanwhile, Happy Harmonies failed to make a success in the theaters, and by 1937, Happy Harmonies and the cartoon's main character Bosko were cancelled by MGM, and MGM had fired Harman and Ising as the head of the animation department and replaced them with Fred Quimby
After Quimby took over, he kept a number of Harman and Ising's staff and created an animated adaptation of the comic book series The Captain & The Kids, which was a flop
In 1939, however, Quimby gained success after cancelling The Captain & the Kids series and rehiring Harman & Ising. After being rehired at MGM, Ising also created MGM's first studio-originated animated star, Barney Bear

Mintz, meanwhile, was still in charge of his own cartoon operation producing Krazy Kat cartoons, and a new series featuring a boy named Scrappy, created by Dick Huemer in 1931. Scrappy was a big break for Mintz and was also his most successful creation too, but his studio would suffer irreparable damage after Dick Huemer was fired from the Mintz Studio in 1933
In 1934, Mintz, like most other animation studios at the time, also attempted to answer Disney's use of Technicolor, and began making color cartoons through the Color Rhapsodies series
; the series was also featured in three-strip Technicolor after Disney's contract with Technicolor, which guaranteed him to be the only animator to use three-strip Technicolor, expired in 1937
However, the series failed to garnish attention, and by 1939, Mintz was largely indebted to Columbia Pictures- who distributed his cartoons since his departure from Universal Pictures in 1929-, and sold his studio to Columbia as a result, and Columbia renamed the studio -which Mintz still managed- as Screen Gems
; Mintz died the following year.
After losing his Aesop's Film Fables series to the Van Beuren Studio in 1929, Paul Terry established a new studio called Terrytoons. Neither the Van Beuren or Terrytoons cartoons were able to compete with the success of some of the other studios, Disney in particular. In 1934, as other studios were putting cartoons in Technicolor to answer to Disney's cartoon series, Van Beuren Studios abandoned its remaining cartoons and answered Disney's use of Technicolor by creating the Rainbow Parade series, which was all color
However, the series was not a success, and by 1936, RKO Pictures-the owner of the Van Beuren Studio- closed the Van Beuren Studio as RKO chose to instead distribute Disney cartoons
However, Disney was not the first animation producer to make an animated cartoon longer than the standard one reel. In 1936, Fleischer Studios produced the first of three two-reel Popeye Technicolor features: Popeye the Sailor Meets Sindbad the Sailor (1936), Popeye the Sailor Meets Ali Baba's Forty Thieves (1937), and Aladdin and His Wonderful Lamp (1939). The Fleischer studio relocated from New York to Miami, Florida in 1938-in order to avoid organized unions, which became a threat to the studio after a five month strike occurred among Fleischer Studio workers in late 1937
- and there the Fleischers produced an animated feature version of Gulliver's Travels in 1939. A small success, it was followed by Mister Bug Goes to Town in 1941, which was a failure. Shortly after this film failed at the box office, Paramount fired the Fleischers from their own studio, which was now completely owned by Paramount; the facility was renamed Famous Studios and moved back to New York. These two Fleischer features were the only American animated features other than Disney's until 1959, when UPA released 1001 Arabian Nights. Other non-Disney animated features made in America were not released before 1962 with Gay Purr-ee (also by UPA). The avant-garde film Heaven and Earth Magic was released the same year, although not theatrically.
As Disney began to concentrate on the production of animated feature films, he did not personally oversee his short cartoons in the manner that he had before. While the Disney short films remained inventive, entertaining, and always featured exquisite animation, the stories began to lag and become predictable. This left an opening for the animators producing cartoons at the Leon Schlesinger studio for release by Warner Bros. The Schlesinger staff produced a series of zany and creative Looney Tunes and Merrie Melodies cartoons which have influenced animators and other filmmakers for generations afterwards. After Daffy Duck was created in 1937, in the cartoon Porky's Duck Hunt, he would add even more success to Warner Bros cartoons and replaced co-star Porky Pig as the studio's most popular animated character
Bugs Bunny would also and add to studio's success after being created in the successful, as well as Academy Award nominated, cartoon A Wild Hare in 1940, and quickly replaced Daffy as the studio's top star
Because of Bugs Bunny, the Schlesinger studio now had risen to new heights, and Bugs quickly also became the star of the color cartoons Merrie Melodies, which had previously been used for one-shot character appearances. Warners' cartoon directors came into their own at this time, and the 1940s cartoons of Friz Freleng, Chuck Jones and Bob Clampett are now considered classics of the genre. By 1942, Warners shorts had surpassed those of Disney in popularity
As motion pictures drew audiences away from their radio sets, it also drew talented actors and vocal impressionists into film and animation. Mel Blanc gave voice to many of Warner Bros. most popular characters, including Bugs Bunny, Porky Pig (starting in 1937), and Daffy Duck. Other voices and personalities from vaudeville and the radio era contributed to the popularity of animated films in the Golden Era.
Cartoons of this era also included scores played by studio orchestras. Carl Stalling at Schlesinger/Warner Bros. and Scott Bradley at MGM composed numerous cartoon soundtracks, creating original material as well as incorporating familiar classical and popular melodies.
Many of the early cartoons, particularly those of Disney's Silly Symphonies series, were built around classical pieces. These cartoons sometimes featured star characters, but many had simple nature themes.
With the advent of the 1940s, two major events evoked change in the status quo of the Hollywood cartoon studios. The first was the entry of the United States into World War II, and the mobilization of all the studios (including their cartoon divisions) to produce propaganda material to bolster public confidence and encourage support for the war effort. The second was the Disney animators' strike of 1941, which severed many ties between Walt Disney and his staff, while encouraging many members of the Disney studio to leave and seek greener pastures. Two Disney animators who left during the strike named Frank Tashlin and John Hubley had also obtained jobs at Screen Gems as well, where Tashlin served as head producer and Hubley served as a director for studio
; Tashlin helped Screen Gems gain more success, and also maintained his position until Columbia Pictures released him from the studio in favor of Dave Fleischer in 1942
Some of these former Disney employees also went on to form UPA, a studio which would have a significant impact on the look of cartoons throughout the 1950s. Other Disney staff members migrated to competing cartoon studios, including MGM, Paramount, and Warner Bros.
The major Hollywood studios contributed greatly to the war effort, and their cartoon studios pitched in as well with various contributions. Over at the Fleischer studios, Popeye the Sailor joined the Navy and began fighting Nazis and "Japs"; while the Warner Bros. studio produced a series of Private Snafu cartoons especially for viewing by enlisted soldiers.
The war was the second of two major blows to shake Walt Disney's empire, as the US Army had seized Disney's studio as soon as the US entered World War II in December 1941
But while Disney lagged, it didn't fall. Disney contributed to the war effort with propaganda shorts and a feature film entitled Victory Through Air Power . Victory Through Air Power was a box office failure and the studio lost around $500,000 as a result
The required propaganda cartoon shorts were also not as popular as Disney's regular shorts, and by the time the Army ended its stay at Disney Studios when the war ended in 1945, Disney struggled to restart his studio, and had a low amount of cash on hand
Further Disney feature films of 1940s were modestly-budgeted collections of animated short films, including Make Mine Music, Fun and Fancy Free, The Adventures of Ichabod and Mr. Toad Melody Time, and The Three Caballeros. The most ambitious Disney film of this period was Song of the South (1946), a film blending live-action and animation which drew criticism for racial stereotyping in later years. During this era, Mickey's popularity sharply declined as well
However, during this era, Donald Duck's popularity would remain very high among theater audiences
; even by 1938, Donald had even become so popular that polls showed he was even more favored than Mickey Mouse
In 1949, he had replaced the fading Mickey Mouse as Disney's most popular character 
The Schlesinger studio, meanwhile, hit its stride and saw a surge in popularity that would propel its animation studio through the next fifteen to twenty years. These years are seen as the time when Friz Freleng and Bob Clampett reached the peak of their creativity. Clampett in particular brought the six-minute animated cartoon to a level of wild surrealism, directing noted cartoons such as Porky in Wackyland (1938), Tortoise Wins By a Hare (1943), and Coal Black and de Sebben Dwarfs (1943).
Leon Schlesinger sold his studio outright to Warner Bros. in 1944. In 1946, a dispute with the studio led Clampett to leave Warner Bros. and strike out on his own. He worked as one of the pioneers of children's programming in the newly-born field of television, where he created the popular Time for Beany television show.
At MGM, directors Will Hanna and Joe Barbera scored a hit with their short film Puss Gets The Boot, which was nominated for an Oscar, and they then set themselves to producing a long-running series of Tom and Jerry cartoons that won accolades for MGM - as a string of Academy Awards that was unmatched by any other studio save Disney. After appearing in Puss Gets the Boot, Tom & Jerry quickly became the stars of MGM cartoons
Meanwhile, Tex Avery left Warner Bros. after a dispute with Leon Schleisinger, and he came to MGM and revitalized their cartoon studio with the same spark that had infused the Warner animators. Between the Tom and Jerry series and Tex Avery's wild, surreal masterpieces of his MGM days (including a saucy, sexy Red Hot Riding Hood series that set new standards for "adult" entertainment in Code-era cartoons), MGM was finally able to compete with Disney (and now Warner Bros.) in the field of animated cartoons.
Another thriving studio in the 1940s was the Walter Lantz studio. Since Oswald had worn out his welcome, Lantz and his staff worked on several ideas for possible new cartoon characters (among them Meany, Miny and Moe and Baby-Face Mouse). Eventually one of these characters clicked - his name was Andy Panda
, who aired in Technicolor. However successful Andy was, it was not until the character's fifth cartoon, Knock Knock that a real breakthrough character was introduced. This was none other than the great Woody Woodpecker, who become Lantz's most successful creation ever 
The winds of change also blew in the direction of the Fleischer studios, though the results were not as beneficial and inspiring as the events at MGM. In May 1941, the Fleischers gave Paramount full ownership of the studio as a collateral to pay off their debts left from the loans they obtained from the studio to make unsuccessful cartoons like Stone Age, Gabby, and Color Classics, though they still maintained their positions as heads of their studio's production
Paramount also requested the brothers to submit undated letters of resignation in order for this acquisition to take place, as the brothers were drifting apart due to disputes
Under Paramount rule, the Fleischers brought Popeye into the Navy and contributed to the war effort, and would gained more success by beginning a series of spectacular Superman cartoons (the first of which was nominated for an Oscar) that have become legendary in themselves. Despite the success Superman gave the studio, a major blow to the studio would occur as Max and Dave Fleischer were no longer speaking to one another due to their disputes
In 1942, after Mr. Bug Goes Town failed at the box office and Dave Fleischer, still maintaining his position as co-chief of his studio, had left Fleischer Studios to run Columbia Pictures' Screen Gems cartoons, Paramount Pictures suddenly accepted the brother's letters of resignation and expelled the Fleischers from their positions as the head of the cartoon studio
In a move that remains controversial to the present day (though it has not been closely examined by film historians), Paramount took over the Fleischer studio completely and brought it under the fold of their own studio, renaming it Famous Studios and continuing the work that the Fleischers began, and also discontinued the expensive Superman cartoons. The departure of the Fleischers had an immediate effect on the studio: while the Paramount cartoons of the war years continued to be entertaining and popular, a decline in story quality began that would become more and more evident as the decade came to a close.
The exclusivity of animation also resulted in the birth of a sister industry that was used almost exclusively for motion picture special effects: stop motion animation. In spite of their similarities, the two genres of stop-motion and hand-drawn animation rarely came together during the Golden Age of Hollywood. Stop-motion animation made a name for itself with the 1933 box-office hit King Kong, where animator Willis O'Brien defined many of the major stop motion techniques used for the next 50 years. The success of King Kong led to a number of other early special effects films, including Mighty Joe Young, which was also animated by O'Brien and helped to start the careers of several animators, including Ray Harryhausen, who came into his own in the 1950s.
George Pál was the only stop-motion animator to produce a series of stop-motion animated cartoons for theatrical release, the Puppetoon series for Paramount, some of which were animated by Ray Harryhausen. Pál went on to produce several live-action special effects-laden feature films.
Stop motion animation reached the height of its popularity during the 1950s. The exploding popularity of science fiction films lead to an exponential development in the field of special effects, and George Pál became the producer of several popular special-effects laden films. Meanwhile, Ray Harryhausen's work on such films as Earth vs. the Flying Saucers, The Seventh Voyage of Sinbad, and The Beast From 20,000 Fathoms drew in large crowds and encouraged the development of "realistic" special effects in films. These effects used many of the same techniques as cel animation, but still the two media did not often come together. Stop motion developed to the point where Douglas Trumbull's effects in 2001: A Space Odyssey seemed lifelike to an unearthly degree.
Hollywood special effects continued to develop in a manner that largely avoided cel animation, though several memorable animated sequences were included in live-action feature films of the era. The most famous of these was a scene during the movie Anchors Aweigh, in which actor Gene Kelly danced with an animated Jerry Mouse (of Tom and Jerry fame). But except for occasional sequences of this sort, the only real integration of cel animation into live-action films came in the development of animated credit and title sequences. Saul Bass' opening sequences for Alfred Hitchcock's films (including Vertigo, North by Northwest, and Psycho) are legendary, and he had several imitators.
Bosustow, Hilberman, and Schwartz named the new studio as Industrial Film and Poster Service, or IFPS
Artistically, the studio used a style of animation that has come to be known as limited animation. The first short from the newly-formed studio was Hell-Bent for Election (directed by Warners veteran Chuck Jones), a cartoon made for the re-election campaign of Franklin D. Roosevelt. Although this new film was a success, it did not break the boundaries that Hubley and his staffers had hoped. It wasn't until the third short, Bobe Cannon's Brotherhood of Man, that the studio began producing shorts aggressively stylized in contrast to the films of the other studios. Cannon's film even preached a message that, at the time, was looked down upon – racial tolerance. By 1946, the studio was renamed as United Productions of America (UPA), and Hilberman and Schwartz had sold share of studio stock to Bosustow 
In 1948 UPA also found a home for itself at Columbia Pictures and began producing theatrical cartoons for the general public, instead of just using propaganda and military training themes
; UPA also earned itself two Academy Award nominations during its first two years in production. Columbia was also looking for a new cartoon production company after the unsuccessful cartoon series Screen Gems -which was scarred after Columbia Pictures fired Frank Tashlin in favor of Dave Fleischer in 1942 - closed in 1946
From there, the UPA animators began producing a series of cartoons that immediately stood out among the crowded field of mirror-image, copycat cartoons of the other studios. The success of UPA's Mr. Magoo series made all of the other studios sit up and take notice, and when the UPA short Gerald McBoing-Boing won the Oscar, the effect on Hollywood was immediate and electrifying. The UPA style was markedly different from everything else being seen on movie screens, and audiences responded to the change that UPA offered from the repetition of usual cat-mouse battles. Mr Magoo would go on to be the studio's most successful cartoon character
However, UPA would also suffer a major blow after John Hubley was fired from the studio during the McCarthy Era in 1952, due to suspicions of having ties to Communism
; Steve Bosustow took over, but was not as successful as Hubley, and the studio was eventually sold to Henry Saperstein 
By 1953, UPA had gained great influence among the industry. The Hollywood cartoon studios gradually moved away from the lush, realistic detail of the 1940s to a more simplistic, less realistic style of animation. By this time, even Disney was attempting to mimic UPA. 1953's Toot, Whistle, Plunk and Boom in particular was an experiment in stylization that followed in the footsteps of the newly-formed studio.
The MGM cartoons of the 1950s also continued to win Oscars. The Tom and Jerry series developed two more Oscar winners—The Two Mouseketeers (1952) and Johann Mouse (1953). Tex Avery also continued at MGM until 1953, when, after a brief tenure at the Lantz studio, he left the animated shorts business to go into commercial animation. By then, the studio found itself facing budgetary problems
By 1957, the MGM studio had closed, after MGM decided to reissue the older cartoons instead of making new ones. Finances also became an issue for Lantz Studios, which moved to United Artists after failing to renew its contract with Universal, and by 1948, that studio closed as well. However, the studio reopened in 1950, releasing cartoons Lantz and his staff had begun work on prior to the studio's shutdown, with Lantz's wife Grace Stafford now serving as Woody's new voice. By the 1960s, Lantz and many other theatrical cartoon producers (such as Famous Studios, Disney Studios, Terrytoons, and Warner Bros.) began contending with the medium of television.
In 1946, the animation union of the time negotiated a pay increase on 25%, making the cartoons more expensive to produce on a general basis.
After the 1948 verdict following the United States v. Paramount Pictures, Inc. case, there was no longer a booking guarantee on the theatres for cartoons from any of the studios, making it a more risky business and because of this less resources were invested in the theatrical shorts, causing a gradual decline. Screen Gems, Ub Iwerks and Van Beuren and others had already closed their animation studios before 1950, and as already mentioned the same thing happened to Metro-Goldwyn-Mayer cartoon studio in 1957.
Disney's animated feature films continued to draw in large crowds through the 1950s. After a series of feature films in the late 1940s that were essentially series of short cartoons strung together, the studio saw a return to the successful formula of adapting fairy tales and children's stories to animation. Disney produced a number of classic films in the 1950s, including Lady and the Tramp, Peter Pan, Cinderella, Alice in Wonderland (which wasn't a commercial success), and Sleeping Beauty, though even Disney found it impossible to reproduce the stunning realism of Fantasia, Pinocchio and Bambi. Cinderella was a big break for Disney, and would become Disney's most successful film since Snow White and the Seven Dwarfs
Upon building Disneyland, Walt Disney regained a huge amount of popularity among the public
, and
turned his focus at producing his longest movie; Sleeping Beauty. However, the failure of Sleeping Beauty almost bankrupted the studio, resulting in a reduced staff and less money invested in animation projects.
In 1960 Disney (soon followed by other studios) replaced traditional hand-inking with Xerography, a technique that resulted in films where the drawings had a "sketchier" look. Films like 101 Dalmations, The Sword in the Stone, and The Jungle Book in the 1960s had that sketchy animation.
With television's growing popularity, there began a decline in moviegoing. To face the competition from TV, the theaters did what they could to reduce their own costs. One way of doing this was booking features only and avoiding the expenses of shorts, which were considered as unnecessary and too expensive. Those few shorts who did find their way to the theaters despite this, had to be cheap, and because of that lacked the quality of their predecessors. The Golden Age was over and the state of American animation was changed forever.