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The Lord of the Rings (1978) More at IMDbPro »

The director had originally proposed a three-part adaptation to United Artists, the then-current rights holders. UA negotiated down to two films, and later refused to fund a sequel.

The original title was "The Lord of the Rings Part One." After the film was completed, the studio told the director that no one would pay to see half of a film. The director objected to the name change, because it would confuse audiences into thinking that they would be getting the whole story. Nevertheless, the studio went ahead and issued the film as J. R. R. Tolkien's The Lord of the Rings, against the director's objections.

The name change from Saruman to Aruman was a deliberate choice to avoid confusion with the similarly-named villain Sauron. However, for some reason the name change was not consistently applied, resulting in a character who was alternately referred to by two different names, which likely caused more confusion than it solved.