Van Diemen's Land (FFilms)
In 1822, eight Irish and English convicts escaped from the hellish penal colony Macquarie Harbour in Tasmania. As they were all originally from urban areas, none of them had any idea how to survive in the harsh Tasmanian wilderness. They had one woodcutting axe between them, and over the next few months they all turned on each other and resorted to murder and cannibalism. Only one man lived to tell about it and his name was Alexander Pearce.
This 2009 independent Australian film is I think about the closest anyone can get to experiencing this in all its gritty detail. The movie seems to be closely based on the non-fiction book Hell's Gates: The terrible journey of Alexander Pearce, Van Diemen's Land cannibal by Paul Collins which I've read, as well as contemporary sources and Alexander Pearce's own two (slightly differing) confessions. Filmed on location in the primordial Tasmanian wilderness in both English and Irish Gaelic and using essentially only eight actors, I'm certainly not able to find anything inaccurate about it aside from some minor abbreviations of the plot. It's a gritty, violent, realistic and suspenseful thriller about a horrific incident that really happened and I would highly recommend it to anyone interested in this historical time and place or who enjoys movies with those themes.
Aguirre, the Wrath of God (Amazon)
Like Van Diemen's Land, this 1972 movie by the German director Werner Herzog is another film shot very much on location in the actual Amazon River where it is set. It depicts an ill-fated and hellish Spanish conquistador expedition down the Amazon in search of El Dorado in 1560-61 which quickly descended into mutiny and systematic murder, as a psychopathic veteran conquistador named Lope de Aguirre overthrew the expedition's leader, personally killed or had his henchmen kill anyone who resisted his authority and then planned to overthrow the Spanish Empire in the New World and make himself ruler. Aguirre even sent a strange letter to the Philip II of Spain declaring his eternal rebellion and giving himself outlandish titles like "Wrath of God," "Prince of Freedom," "King of Tierra Firme," and "The Traitor" and "The Wanderer."
Probably needless to say, the real Lope de Aguirre seems to have been pretty mentally unhinged, and one of the reasons I love this movie so much is that the actor who plays him was in fact quite unhinged and psychopathic himself and most of all famous for his insane screaming fits of rage that have to be seen to be believed. The relationship between the German actor Klaus Kinski (who plays Aguirre) and director Werner Herzog is extremely complicated but it was often filled with violent threats and mutual hatred. During the filming of Aguirre, Kinski and Herzog were both armed with guns and Kinski shot off a native extra's finger because he was annoyed by the sound coming from a hut. At one point when Kinski threatened to leave the production over his grievances with Herzog's directing style, Herzog claims that he threatened to shoot Kinski unless he returned. These incidents are discussed in Werner Herzog's 1999 documentary My Best Friend specifically about his relationship with Kinski (this is a clip of Herzog talking about Kinski). In his personal life, Kinski has also been accused of far worse things which I won't go into here. I think it's impossible to know what the real Aguirre was really like in every detail, but I can't think of a better person to portray the deranged paranoid megalomaniac that he was on screen.
As for the more technical historical accuracies of the film, although it is ostensibly about Aguirre's 1560-61 expedition down the Amazon, it in fact combines many events from both that expedition as well as the conquistador Francisco de Orellana's 1541-42 expedition some twenty years earlier. A short list of these mergers are how the expedition begins by crossing the Andes to reach the Amazon basin, which is taken from the 1541-42 expedition, while the 1560-61 expedition was able to travel by boat from the beginning. The premise of Aguirre taking control of the expedition when he is sent down the river with a smaller party and gets carried away by the current is also taken from the 1541-42 expedition. The ending of the movie in which Aguirre is one of the last survivors while his crew is shot to death by native arrows seems to be taken from the reported end of Francisco de Orellana during his second expedition in 1546, while Aguirre was eventually killed by his own men after being surrounded by Spanish soldiers in Venezuela. Also the Spanish Dominican priest Gaspar de Carvajal who narrates the movie and is portrayed as being part of Aguirre's expedition is in fact based on the priest who accompanied Orellana and wrote an account of that expedition.
Most of the other events portrayed in the film as occurring during Aguirre's expedition do seem to be based on fact. Aguirre really did take control of the expedition in essentially the way portrayed, behead people without warning for slight offenses and write that bizarre letter to the King of Spain which is portrayed in the film.
A historical book I would highly recommend about these events is The Golden Dream: Seekers Of El Dorado by Robert Silverberg which contains very detailed accounts of both Aguirre and Orellana's expeditions down the Amazon in the 16th century.