Little known outside of Canada, the Battle of St. Lawrence took place between May of 1942 and November of 1944. For over two years, the Kriegsmarine waged a major operation against Canadian and British shipping. When the last German U-boat finally surrendered in 1945, the Canadians had lost 23 merchant ships and 4 warships.

It’s not like the British filmmaker Michael Powell didn’t warn them.

In some ways, 49th Parallel is straight up propaganda designed to galvanize the North American public into the supporting war against Germany. Featuring performances by Lawrence Olivier, Anton Walbrook, and Eric Portman, it’s also an effective film in its own right that holds up today. Foreshadowing the later Battle of St. Lawrence, 49th Parallel begins with a German U-boat sinking a Canadian oil tanker at the mouth of the St. Lawrence River, then slipping into Hudson Bay to evade an attack by the Royal Canadian Air Force. Shortly after they surface near Churchill in Northern Manitoba, and a reconnaissance party sets off in a launch to search for food and supplies, another Canadian air attack destroys the submarine and leaves the captain, and eight other crewman stranded in Canada, their only chance at escape the 49th Parallel, the demilitarized border with the then neutral United States.

Unlike Captain Langsdorff in Powell’s later film The Battle of the River Plate, a straight, bourgeois navel officer who obeys the rules of war, Captain Hirth and his crew are hard core Nazis, stone cold true believers in the fascist cause. Being stranded in Canada, which they see as a a soft, decadent, multicultural democracy ripe for the picking, is an opportunity. It’s 8 Aryan superman against 11 million multicultural democrats. They will steal what they need at gunpoint, shoot anybody who resists, and pick up as many converts to the cause of National Socialism as they can find. When they get back to Germany, Hitler will pin the Iron Cross on Hirth, and they will all receive a hero’s welcome.

For Michael Powell, Captain Hirth and his crew’s trek across Canada is a test. How will citizens of a democracy act when their comfortable lives are interrupted by actual Nazis staring down at them from the barrel of a gun? Not surprisingly they all come through test fairly well. The last thing a British filmmaker was going to do in 1941 was insult Canadians or Americans. So we are treated to a series of vignettes where democracy successfully resists fascism. The devil, nevertheless, is in the details. If 49th Parallel were only a rousing call to arms against Hitler, it might no longer be relevant. But it’s something much more, a complex, nuanced affirmation of a democracy that we, perhaps, no longer have. In some ways, 49th Parallel is a message in the bottle to a future North America, a North America that might not resist fascism quite as well as it did in 1941.

The first Canadians Hirth and his crew run into are Johnny, a French Canadian trapper played by Lawrence Olivier, Nick, his Inuit sidekick, and a storekeeper played by the Scottish actor Finlay Currie. In other words, it’s a pretty good ethnic cross section of old Canada. The segment was also heavily censored when 49th Parallel was released in the United States in order to avoid alienating Southern Democrats. After Nick leaps to Johnny’s defense and is rewarded by having his skull split open by Nazi rifle butts, Captain Hirth explains to his remaining white, French and Scottish, hostages that Eskimos are an inferior race, “one step below Jews and only one step about Negroes.” Apparently the United States was ready for an anti-fascist, but not an anti-racist movie. Hirsch then tries to recruit Johnny, showing him a copy of Mein Kampf and explaining to him how Germany was ready to liberate French Canadians from their Anglo Saxon oppressors. Help the Germans invade Canada and French Canada will once again be able to have their own culture, their own schools, their own religion.

Lawrence Olivier’s portrayal of a French Canadian frontiersman has been criticized for being silly and over the top, but that’s ridiculous. As someone who’s spent time in a remote Alaskan fishing town, I find Johnny a very familiar type. Everything about Olivier’s performance, his expansive, insolent body language, his expressive yet ungrammatical way of speaking, his uneducated, yet quick, intuitive way of speaking gets at the heart of what a genuinely free man is like. Having spent the past year in the woods trapping animals and collecting firs, not having seen a newspaper for months, Johnny has no idea Canada is at war with Germany. When he reads about German war crimes in Poland, he doesn’t believe it. He wouldn’t do anything like that, so why would people in Germany? Besides, he tells the store owner, all governments are pretty much alike anyway, corrupt institutions best avoided. The war doesn’t doesn’t concern him. “Why should Canada go to war for a bunch of Poles.”

Five minutes later he’s face to face with an actual Nazi.

Johnny’s ability to see through Hirth’s propaganda is a great example of how an intelligent, apolitical man comes to terms with a political reality he can no longer avoid. He finds Hirth’s proposal laughable. Why should he join the Nazis? The Anglo Canadians may be the dominant ethnicity in Canada, but French Canadians already get to keep their own schools, their own church, their own way of life. Why do they need a bunch of Germans to give them what they already have? And how about the Poles, he asks, do they get to run their own country? When Hirsch explains that “well that’s different. It’s the new German world order,” Johnny just laughs. “Maybe your Mister Hitler isn’t too smart,” he says. All the while, of course, Johnny, who is seething with rage over the way the Germans murdered Nick — “you call Eskimos animals but I never treat my huskies the way you treated Nick so maybe you the animals” — is looking for an opportunity to strike back. But it’s useless. It’s Johnny and one old man versus eight heavily armed German invaders. He ends up lying on the bed, shot through the head, and denied his rosary or the last rights by a German guard who sneers at Christianity. So much for the French in Canada being allowed to keep their religion.

One of the Germans, however, a crewman named Vogel, crosses himself and gives Johnny the rosary just before Johnny dies. He becomes the focus of the next segment of 49th Parallel. Can a man who’s lived under a fascist government for 8 years be redeemed? Can a nation fallen under the spell of Hitler be saved? Vogel is a deeply conflicted man. Just before the 8 men continue south on their journey to the American border, and after Vogel gives Johnny his rosary, he furiously scratches swastikas all over the walls of the remote outpost, almost as if he wants to apologize to the Fuhrer for his brief relapse into the decadent Christian religion and the decadent concept of mercy.

Nevertheless, when the 8 Germans, now six after an Inuit sniper picks off one of the Aryan supermen and a second dies when they crash a stolen float plane, come upon a colony of German “Hutterite” immigrants, a radical Christian sect similar to the Mennonites, Vogel realizes how much he hates living under the Nazi government. At first, Vogel quite literally can’t understand democratic government. “Who’s your leader?” he asks He’s astonished when that leader, a man named Peter played by the Austrian actor Anton Walbrook, has no power to order people around, that he’s simply an elder, a spiritual guide for people who, in the end, are free to do whatever they choose, to follow whatever profession they like, to come and go as they please. When Peter is called on to speak, however, he proves that he is indeed a “leader,” denouncing fascism and militarism as a plague, and defending freedom and multiculturalism. He also offers Vogel a way out. Surrender to the Canadian authorities, spend a few years in a prisoner of war camp, and then return to the commune as their baker, a profession he followed before the Nazis came to power and to which he desires to return. Sadly Vogel, who gladly accepts their offer, is murder by Hirth, who brands him a deserter and carries out a summary execution.

Vogel’s death is the climax of 49th Parallel, which never again quite reaches the dramatic heights of Peter’s fiery speech against tyranny. There’s a rather silly episode with Leslie Howard as a pompous intellectual, who finds himself able to resist only after the Nazis callously destroy his paintings and his books, and another equally silly episode with Raymond Massey as a Canadian soldier gone AWOL who challenges Hirth to a fist fight after he learns who he is. “Put em up” the Canadian says to the Nazi, who, like any slave, can’t imagine an honest fight man to man and raises his hands as if he’s under arrest. Nevertheless, even though it falls apart dramatic after Vogel’s death, 49th Parallel remains an astonishing travelogue, showcasing the sublimely beautiful landscapes around Banff. So that’s what Canada looked like in 1941? Surely it was something worth fighting for.