[In Aguirre, Wrath of God] Herzog paints his most ambitious canvas…. No blockbuster this, however, despite some imposing set-pieces Herzog's manageable cast is fairly small and it is not long before the paranoid Aguirre dominates proceedings and script alike. (p. 38)
Herzog is at pains throughout to show the reality of the expedition behind the glamorous legend: cannons trundling through muddy swamps, raging rivers to be crossed, sudden death from darts or arrows from the Indians following on the river bank. The metaphor of the journey itself for Aguirre's breakdown is obviously but painlessly applied, and Herzog's film, not at all to its detriment, can be compared with the similar Deliverance of John Boorman. In both the main characters soon take to the river, but where Boorman concentrated more on the suspense of the situation, Herzog assuages the viewer with the savage beauty of the landscape, inserting sudden jabs of violence and paranoia like so many pinpricks.
There is an intangible quality to the film, moreover, which never allows the viewer to become too relaxed. The dialogue, if it may truthfully be described as such, is more in the form of spoken recitative, the characters mouthing rather than conversing, and its stylised, declamatory feel works well with the fantastical side of the expedition. For, despite Herzog's constant reminder of Sixteenth-century realities, there is an abiding sense of the other-worldly throughout the film—a dreamy quality underlined by native pipe-playing and hallucinations made concrete…. The presence of the two women on the journey also affords a contrast between their pristine beauty and calm, and the filth and fatigue of Aguirre and his crew. Although Herzog's film is about one man's paranoia, it is a fantasia on that theme rather than a closely-documented record. If anything, it is too cool, too detached, to make any emotional impact…. A film which can be admired from afar and relished for its memorable moments, most particularly the final shot of a lone Aguirre ranting on the raft as hordes of monkeys clamber over the timbers—as potent a visualisation of madness as one might wish for (pp. 38-9)
Derek Elley, "'Aguirre, Wrath of God'" (© copyright Derek Elley 1975; reprinted with permission), in Films and Filming, Vol. 21, No. 5, February, 1975, pp. 38-9.