Final answer:
The claim that 'Triumph of the Will' warned against joining the Nazi Party is false; it was a propaganda film glorifying Hitler and the Nazi regime.
Step-by-step explanation:
The statement that Leni Riefenstahl's film Triumph of the Will was intended to warn Germans about the dangers of joining the Nazi Party is false. Riefenstahl's film was a propaganda piece commissioned by the Nazi regime, specifically designed to glorify Hitler and the National Socialist movement. It showcased the 1934 Nazi Party rally in Nuremberg and sought to impress upon viewers the power and unity of the Nazi Party, not to serve as a cautionary tale.
If anything, Triumph of the Will was part of a broader propaganda campaign aimed to win the loyalty of the population to the regime and to Hitler personally. The film represented the ideals of a racialized, warlike, and 'purified' German nation, portraying the Nazi message in a positive light to the German public.