When Drover arrives at the mission ball, he is freshly shaved. When he discussed the Wet with Lady Sarah, he has stubble.
While the group rests overnight during their trip to Darwin, Fletcher's guys pour out the gasoline and light it up. When the fire starts, it's pitch black and the stars are visible. When the stampede starts, it's mid-day.
When Sarah asks Flynn to tell her all about Faraway Downs and Fletcher, Flynn pulls out a full bottle of rum. When he opens it in the close-up shot, it's a different bottle, partly full. In the next scene, he holds the open full bottle.
When the rain starts, Drover's coat is over his shoulder, and brown mud spots are all over his shirt sleeve and jacket. In the next shot the spots are gone and his shirt is clean.
After Drover cuts the rope to block Carney's people from loading their cattle, the door goes down right in front of a cow. In the next shot, no cattle are in the passage.
When Nullah (Brandon Walters) and his mother Daisy (Ursula Yovich) evade deportation by hiding in a water tower, the tank is full of holes but it fills up within a few minutes when the wind blows. In fact windmills can take hours to fill a tank with water, even if the wind is blowing strongly, and probably never if the tank has big holes in it.
The Japanese did not land troops on any island near Darwin.
One shot, edited in from Tora! Tora! Tora! (1970), shows the USS Oklahoma and the USS Maryland. No battleships, American or otherwise, were in Darwin during the attack. Smaller warships were there, including American destroyers.
Japanese planes drop torpedoes on land-based targets. No pilot would use a torpedo for a land-based target.
When the refugee boat enters the harbor after the attack, it passes the bombed-out remains of the ship Barossa, lying on her side and burning. In real life, the Barossa, while heavily damaged, was towed to safety and later salvaged.
During the attack scenes, some planes' wheels are retracted while bombing or shooting, others are extended. Aichi D3A "Val" bombers had fixed landing gear. Mitsubishi "Zeke" (or "Zero") fighters had retractable landing gear.
When Drover shows up at the ball freshly shaved, he has no tan line where his beard once was. He spends all of his time out in the intense sun, so the bottom half of his face should be paler.
Early in the film, Drover's truck runs beside some bounding kangaroos. The kangaroos' leg action does not match their speed; the swing backwards stops too soon.
Copper Callahan and his men arrive at Faraway Downs looking for Nullah, and don't find him. However, when they drove up to the ranch, Nullah and Daisy were climbing the water tower ladder, facing the truck. As they leave, two policemen sit in the bed of the truck as it pulls away. People on the station run toward the water tower in obvious distress. Drover climbs the ladder to retrieve Nullah and Daisy, in full view of the police in the truck bed no more than 50 yards away, yet the truck makes no response.
A clip from the beginning of The Wizard of Oz (1939) is shown in plain black-and-white, as is often seen on television. In its original theatrical run, those sequences would've been in sepia-toned black-and-white.
Several newspaper stories, particularly the one about the Never-Never, have a number of repeated paragraphs.
When the cattle drive arrives in Darwin, the British Officer is prepared to sign a contract with the typed date of 01 Sep 1939, the date typed onto the body of the contract is shown as 1940, and the date on the newspaper in the beauty salon is 29 October 1939.
When discussing Nullah's future, Sarah mentions "a wonderful School of the Air." School of the Air is a correspondence course that uses shortwave radio (and, now, the internet) to teach children in the Outback. The Alice Springs School of the Air covers over a million square kilometers. School of the Air started in 1951.
After the title, when the animated globe switches from Australia to Europe, Germany has modern borders. In 1939 the Third Reich included what is now western Poland, East Prussia/Koenigsberg (now Kaliningrad) next to Lithuania, Austria, and Sudetenland.
When Lady Sarah Ashley is on the telephone switchboard in Darwin, she wears a headset invented in the 1960s. Before that, the microphone was on a separate breastplate hung around the neck.
Late in the film, the barman has crates of Victoria Bitter. It wasn't available outside the Australian state of Victoria until the 1970s.
In the first "tent" scene between Drover, Sarah, and the Aboriginal stockmen, Drover speaks to Sarah while cleaning his teeth. His toothbrush has dark bristles in the center, white bristles around the outside, and a pointed end. In 1939, toothbrushes were rectangular, with white bristles.
When Nullah arrives at Faraway Downs and prepares to dismount his horse, someone off-camera is holding the horse by a visible third rein.
When Drover storms away from Faraway Downs after his argument with Sarah, the tracks from the camera truck in front of his horse are clearly visible in the sand.
As Nullah gallops back to Faraway Downs after mounting the horse at the waterhole, a dust trail is visible in front of his horse. Evidently, someone is galloping ahead of him to make sure that his mount will follow.
The night sky in the Outback includes the Big Dipper, which is not visible in the southern hemisphere, especially from Australia. The Southern Cross should have been shown.
When Fletcher gets into the pickup truck to leave Faraway Downs, he gets into the left front seat and drives away with the steering wheel on the left side. Australian traffic drives on the left side of the road, and Australian vehicles usually have the steering wheel and driving controls on the right.
When Copper Callahan first arrives at Fareaway Downs, he introduces himself as "Northern Territory Police". On the map in King Carney's office, which is shown during Lady Ashley's arrival, Faraway Downs is entirely located in Western Australia.
When the Japanese airstrike starts, a priest makes a transmission from Mission Island, and ends it with "over and out". The correct way to end it is "out." "Over" means you're turning the conversation over to the person you're talking to.
The Union Flag is flown upside down in one scene.
During the Charity Ball, the bandleader calls for a foxtrot. The band plays "Begin the Beguine," which is not a foxtrot.
When the Japanese patrol arrives at the beach, they do not see a 30-foot sailboat close enough to shore that little children could walk or easily swim out to it.