Revealing mistake: In the opening scene, when the soldiers and slaves march down the mountain, as the carriage containing Aguirre's daughter passes by the camera, one of the soldier extras just behind the carriage looks directly at the camera. (00:03:38)
Revealing mistake: At one point when the soldiers are walking through the jungle, one of them steps into a trap and is pulled up into the trees to be killed by Indians. However, if you watch this scene carefully, when the soldier (who steps into the trap) walks into frame you can see a wire already attached to his foot leading up into the trees. He doesn't step into a trap. (00:22:26)
Answer: Kinski suffered from mental illness for most of his life. He was given to bouts of unprovoked outbursts and violence. He was eventually diagnosed with psychopathy (antisocial personality disorder). On movie sets, he was notorious for being physically and verbally abusive to the crew, who generally hated him. The sword incident was just one of many. On the production of this film, director Werner Herzog carried a gun on him in the event he had to protect himself or others. It was only because Herzog was a long-time friend that he hired Kinski for acting jobs. Kinski was flat-out crazy. He was eventually unable to get any work as an actor.
raywest ★
Agreed. I forget what film set it was but Kinski also once fired a rifle at a bunch of crew members and blew a guy's finger off. He was unstable.
Jack Vaughan
It was also Aguirre, The Wrath Of God. Kinski was irritated by the noises from a hut where cast and crew were playing cards and, out of anger, repeatedly fired a Winchester rifle into it. One of the bullets took the tip of an unknown extra's finger off.