"Bambi," she whispered, and every now and then she raised her head, listened to the sounds of the forest, and sniffed the wind. Then she kissed her child again and was relieved and happy.

-- from the original Bambi: A Life in the Woods

OK. I know what you want to hear about. You want to hear about what children of the 1940s thought when the hunter shot Bambi's mother.

We'll get to that. But some context will help understand the adult reaction, so let's talk a little about the original Austrian author, Felix Salten, who wrote both the original book as well as the sequel, Bambi's Children.

In 1921, the year before the book came out, he was mostly known as a journalist, writing a column in a Zionist paper with concerns about anti-Semitism and being critical of those who would hide their Jewish heritage. (He did have one famous book, but it was published anonymously: the pornographic Josefine Mutzenbacher from 1906, of a sex worker who "experiences everything a woman can experience" and "regret[s] none of it".) He was also, importantly, a hunter; he had, by his estimate over his life, killed 200 roebucks, and his long forays with nature were what inspired his work:

Bambi would never have come into being, if I had never aimed my bullet at the head of a roebuck or an elk.

He was adamant that "Hunters can be compassionate", and that the act of eating and hunting an animal was akin to an act of veneration, part of the same circle-of-life as other animals. The original novel was far heavier on the circle-of-life aspect, with predators acting like predators would. From Chapter Two:

A long pause ensued. They walked on quietly again until Bambi finally asked with a certain unease: "Are we also going to kill a mouse like that one day?"

"No," his mother replied.

"Never?" asked Bambi.

"Never ever," came the answer.

"Why not?" Bambi asked, very relieved.

"Because we never kill anybody," his mother stated bluntly.

Death is subsumed into a larger pattern. Hunters, the world of people, were essentially deities, referred to as "He", but the most important death is near the end, at the corpse of a hunter:

“Do you see, Bambi,” the old stag went on, “do you see how He’s lying there dead, like one of us? Listen, Bambi. He isn’t all-powerful as they say. Everything that lives and grows doesn’t come from Him. He isn’t above us. He’s just the same as we are. He has the same fears, the same needs, and suffers in the same way. He can be killed like us, and then He lies helpless on the ground like all the rest of us, as you see him now.”

The sequel, Bambi's Children (1939), is even grislier (at least in the original German, the English translation reduces the violence and also removes the section on moose mating season) but importantly, it should noted a hunter character is in that novel as well, intended to be a "humane" hunter, and is modeled after Felix Salten himself. He didn't really consider his writings to be "for children", and wrote to his American publisher that

At this time I beg you most urgently, quite apart from softenings, not to advertise my work as a children’s book or to launch it otherwise in such a way.

To summarize: the original was meant to bring soul and perspective to wildlife, but from someone used to hunting, who didn't step back from depicting animals killing each other, nor being killed by hunters, and the work -- despite becoming a children's classic -- was never really aimed in that sense. (It was, in the late 20s, a Book-of-the-Month club selection along with works like Bernard Shaw's The Intelligent Woman's Guide to Socialism and Capitalism and The Omnibus of Crime as edited by Dorothy Sayers.)

You might also surmised -- based on the date and the author's Jewishness -- Bambi's Children was written when he himself was in peril, having fled to Switzerland from the Nazis. This led to one of the adult reactions, noting similarities between plights of animals and of Jews, with an American critic calling the fox character in Bambi the "Hitler of the Forest". (The actual Nazis had taken notice and also considered it an allegory, banning the original novel in 1936.)

It is perhaps understandable there might be some political reading, given the release date of the movie: 1942.

...

Bambi was a difficult film. It was embarked on the same year as the release of Snow White and the Seven Dwarves (1937) yet came after Pinocchio, Fantasia, and Dumbo. (The rights had been in obtained in 1933 when Salten sold them outright, making $1000 flat. He made no royalties.) Disney went all-in on a desire for realism, and artists spent months in a park sketching from life; as opposed to a cartoonistic squishing and stretching of such mainstays as Mickey Mouse, Disney wanted his movie to look like a real forest.

The script also reflected the desire for a more natural story. Quoting Disney himself:

We were striving for fewer words, because we wanted the action and the music to carry it.

This ended up being successful enough it was criticized; the New York Times called out the clash between cartoon and naturalism, writing that the movie "throws into relief the failure of pen and brush to catch the fluent movement of real photography."

Ticket sales weren't stellar, but WWII essentially was thrashing all the studios; it was also radically different from Disney's prior movies, with no magic whatsoever. (As Disney later said, "when we released that picture and there was a war on, and nobody cared much about the love life of a deer".)

Hunters were the most upset. Any kind of message of hunter-as-caretaker (which is admittedly more of an element in the never-animated sequel, although Dell Comics did a licensed Disney adaptation in 1943) was absent. Before the movie even came out, the editor of Outdoor Life (Raymond J. Brown) had seen a preview and sent a telegram informing Disney that shooting deer in the spring was illegal, and objected to the depiction of hunters as "vicious destroyers of game". He tried to get a foreword put into the film but was unsuccessful, and tried upon the film's release to get hunters to rally.

He was perhaps not being absurd, as there was some public outcry against hunting at the time and it even had effect on policy; the year after the film's release, Aldo Leopold (author of A Sand County Almanac) pushed for an antlerless deer season and was shot down due to the public outcry: in other words, people didn't want hunters to shoot Bambi's mother.

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Get on with it, you cry: were the children of the 40s traumatized?

I would say most definitely yes. The original scene, incidentally, was worse. Donnie Dunagan, the voice of Bambi, had seen the production version which did not have the death offscreen; there was a bullet hole and you could see the mother's face as she was dying. Walt said (as reported by Dunagan):

Take that out. Just suggest that the mother was shot.

Dunagan also reports, upon showing the final movie, "mothers put their hand over the children’s eyes".

The most vivid report I've found from not long after the movie's release (1949) is from Mr James Kenyon at the floor of Parliament; this was in reference to juvenile policies in general, and he was telling an anecdote:

A few weeks ago I took my two daughters, who are children, to the pictures to see a film called "Bambi" ... It was a children's matinee and the cinema was packed with children. Much is said about juvenile delinquency, but I was cheered when I saw the reactions of the children to the film: the happy, joyous, and lovable scenes in that film called forth their admiration and joy. When it came to the hunting scene, when the dogs were there and the animal was shot, the shock and horror that went through the cinema could be felt. I realised then ... that the heart of our children, the children of the nation, is sound. They will stand for the things that are good, true, kind, clean and wholesome while they will revolt against that which is cruel, merciless and unclean.

Stephen King famously called Bambi the first horror movie he ever saw.

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Lutts, R. H. (1992). The trouble with Bambi: Walt Disney's Bambi and the American vision of nature. Forest and Conservation History, 36(4), 160-171.

Reitter, P. (2015). Bambi's Jewish Roots and Other Essays on German-Jewish Culture. United Kingdom: Bloomsbury Academic.

Tobias, R. B. (2011). Film and the American Moral Vision of Nature: Theodore Roosevelt to Walt Disney. United States: Michigan State University Press.

Whitley, D. (2016). The idea of nature in Disney animation: From Snow White to WALL-E. Routledge.