TL;DR: Let's say I want a particular chapter to be nostalgic in a way that makes the reader miss a time they weren't even a part of, how would you go at it? I have a few ideas but I'd be interested in hearing yours. This story is happening during ww2, so I'm trying to turn the prelude into a narration of when things were "easy and good" (only I'd like to do so without mentioning the war). I used to think that the best way to go at it was to reflect on what makes people nostalgic, but since we're all different, I think I should rather consider the more technical aspects on driving someone to feel nostalgic, if that makes sense? I know if this were a movie, I'd use a nice little song and beautiful sights, but since I can't do that, I'll have to figure out a way to implement those things into words. I've also been thinking that character's personalities might play a big role into this as well. In movies, to make the audience nostalgic they sometime show some briefs personality quirks about someone, maybe to make them feel more real? Maybe because the only way we can feel nostalgic about something is if it reminds us of us or someone we know... I'm rambling lol but thanks!
A quote that appeared at the time you're intending to inspire nostalgia towards? An "old wives" tale that might have been handed down through generations? First line of a well-known poem or a book from that era?* All of these could be placed as a sub-heading. * Just check copyright issues first and/or ensure you include the title and author of the book/poem.
Nostalgia is pretty subjective. My sister romanticizes the 90s, while on the other hand, I reminisce on the early-to-mid 2000s. Considering your setting is taking place in WWII, it would be difficult for a modern audience to understand the nostalgia a character would have before the war. I don't know how one would measure nostalgia on a technical level, but I can suggest that you simplify the nostalgia; in essence, have a character reminisce having breakfast without worrying about rations, or another character remembering being able to walk around the town/city freely without trouble. Make everyday things absent. My two cents.
I was just reading about the 30 year nostalgia cycle, and it seems like creators make things that they themselves are nostalgic for. Think IT, Stranger Things, and Ready Player One, all 80's stuff. Personally, I was born in 80, s0 I was a little young. Those shows strike me as odd or interesting, rather than triggering real nostalgia, and I lived it. I'm looking forward to the 90's callbacks. The thirty year cycle can happen twice, calling back to call backs. Look at games like Fallout, which is full of references to the 50s, but not the real 50s that older people remember. Not the fifties that the 80's remembered in TV, but a creepy deconstruction of the view of the 50s that people had in the 80s. It's weird, and it is suppose to be weird, because it you grew up in the 80s you sort of remember how the 50s were when America was "great." Edit: so my point is that I don't know if you can make someone feel nostalgic unless they are really nostalgic, but if you write about what you are nostalgic about, your readers will be the people who share those feelings with you.
Just about everyone with living memories of the WW2 era is dead now, so hitting a nostalgic note will be difficult.
The problem you're up against is, if you're not mentioning the War, and "things were easy and good" you're not mentioning the Depression that the war ended, so you're either going to have a false, highly sanitized version of the '40's, or else your characters will have to be so wealthy neither of those events would touch them. ETA: Not to mention all the stuff in Europe that was going on with the guy with the mustache and his cohorts "before the war".
It'll be very difficult to bring an actual nostalgic feeling to the reader. Not only because none of them lived in the time you want them to be nostalgic about but also because it is so highly subjective and individual. For me, it is usually, small things that trigger that feeling. A certain sound or smell. The taste of chocolate and strawberry brings on a huge wave every time and I don't even know why. So I'd say, think about what makes you nostalgic and instead of implementing these things themselves, have your characters express that feeling and try to have your readers connect to that. Maybe over something that many people can relate to, like objects, songs or food that carry childhood memories.
Timeless nostalgia is youth. (as long as you are not a kid anymore) So remembering things from when you were a kid. When I was a boy, there was always ice in the winters so you could skate. When I was a boy there must have been more cream in the ice cream, it was so smooth. When I was a young man all girls were pretty. This works in any time period.
I think you can make a character nostalgic, but I'm not sure it's really a good plan to set out trying to make readers feel the same. And how would you ever even know how all your readers feel once your book is out there? Even your movie examples wouldn't bring up those feelings for everyone if they did for anyone. I like to focus on the story at hand and give the readers a good one. How they feel... I'm just hoping they'll feel like they just read a good story. So, give them that -- a good story.
"Easy and good" might not be the best way to go about it. A large factor of nostalgia is yearning for yesterday's trite struggles. There are universal ideas that may resonate: family conflict, a difficult boss, financial struggles, manipulative 'friends.' You know our hero has experienced a rough paradigm shift when he misses something like regular hard labour and/or hopeless squalor.