Completed in less than a month in order to fulfill William L. Snyder's licensing contract with the J.R.R. Tolkien's estate. The film was screened once in a Manhattan theater on June 30, 1966, the day the contract expired.
The Princess in called "Milovana", which means beloved woman' in Czech. The film was produced in Czechoslovakia.
The film depicts the Lonely Mountain from Tolkien's stories, but does not mention its other name. The novels call it Erebor, a Sindarin term.
The film was considered lost for decades, until it was discovered by the son of producer William L. Snyder. In 2012, he released the film on YouTube. It was the first time the film became available to the general public.
In the novel, the Trolls are turned to stone when exposed to sunlight. Their counterparts in the film are instead turned into dead trees when exposed to sunlight.