Many parents were alarmed at the bleakness of the film, having taken their children thinking it was a film along the lines of a Walt Disney cartoon.
The CIA obtained the film rights to "Animal Farm" from George Orwell's widow, Sonia Orwell, after his death and covertly funded the production as anti-Communist propaganda. Some sources assert that the ending of the story was altered by the CIA (in the book, the pigs and humans join forces) to press home their message, but it is equally possible that the more upbeat ending of the movie was an artistic decision, to give the film more audience appeal.
The head of the CIA operation to obtain the film rights was none other than E. Howard Hunt, later famous as US President Richard Nixon's Watergate burglar. As part of the deal, Sonia Orwell requested that she get to meet her idol, Clark Gable; this was arranged.
A large portion of the budget ($300,000 out of a cost of over $500,000) was supplied by the US Central Intelligence Agency, Office of Policy Coordination, through one of its shell corporations, Touchstone Inc.
To make the film, Halas-Batchelor's company was expanded to make it the largest animation unit in Western Europe.