I'll leave discussion of the intricacies of military minutia to other commentators here, but the film's characterization of Napoleon is somewhat problematic. It is not so much a case of inaccuracy as one of tone. Rod Steiger's scenery-chewing Emperor is a solitary figure prone to shouting and haranguing his generals while storming around in a great coat, a cinematic image that begs comparison to Hitler. For example, contrast this Waterloo scene starting at 1:20 to this memed-to death scene from Downfall and other cinematic depictions of Hitler that portray him as a megalomaniac figure who believed his past martial successes could trump reality. Although Steiger's Napoleon lacks the misanthropic edge common to cinematic depictions of Hitler, the film invites this comparison Napoleon's speech to his guard has a lot of the familiar shouts and stage tricks like focusing on individual faces that were common to the filmed speeches given by Hitler. This is stark contrast to the film's depiction of Wellington, who is humanized, genial, and comradely to his subordinates.

The comparison of Napoleon to Hitler was something that begun in the 1930s and became increasingly common during the war. British films like That Hamilton Woman drew explicit parallels to Britain's position in the Napoleonic Wars to its position facing off against Hitler. Waterloo fits very much within this trend. The problem of course is that likening Napoleon to Hitler is an imperfect comparison at best and tends to generate more heat than light. Napoleon's goals and methods of rule were quite different than Hitler and Napoleon's Weltanschauung was firmly rooted in Enlightenment precepts. Comparing Napoleon to Hitler often erases or fudges those features of their personality and rule that made each historically unique.