Capturing an Era

A while back, I came across this post on Love Your Movies, arguing that Saturday Night Fever was a “time capsule” for the 1970s: “a movie that captures perfectly the feeling and times of that era. the music, the clothes, the voice.”
Having lived through the 1970s, I disagreed. The 1970s, for all the crap they get, were a lot of things: Disco dancing, Star Wars, Watergate, the Vietnam War, terrorism (well over a thousand bombings in the first couple of years), The Godfather, The Exorcist, the oil crisis, cable TV stations (stuff like HBO and The Movie Channel were very novel back then), the Kent State killings in 1970, Roe vs. Wade, All in the Family …
That being said, I agree with the author in comments that SNF does do a good job capturing a particular segment of that decade’s culture. And that’s the most any film or book can do without a panoramic approach.
To really get a time capsule of an entire decade take scope, because there’s no decade where everything can be summed up easily. There were probably more Young Republicans in the 1960s than hippies grooving at Woodstock. The 1950s had their conformist men in grey flannel suits, but it also had Beatniks, the Korean War, the start of comic books’ Silver Age, a gay rights’ movement.
Scope is the big blockbuster novel that ranges all over, runs throughout the decade and includes a big cast: Conservative politician father, rebel son, black activists, one of Jimi Hendrix’s groupies, a New Wave SF writer, a typical sitcom writer, a military officer—or any mix that gets the whole range of the era. And it would need to run through the whole era. You see some of this in Harry Turtledove’s World at War books, which criss-cross the entire WW II world to show how it copes with an alien invasion.
Alternatively, you take a slightly narrower scope: Not an entire world but maybe the military, or advertising (I’d make a reference to Mad Men but I just can’t get into the show) or theater or movies (the book Pictures at a Revolution shows how much those changed in the 1960s).
Or you focus on a particular strand, as Saturday Night Fever does, and you do it well enough to capture and define it.
Or (for historical writing), you work with the image and stereotypes of the era. My short story And He Bought a Crooked Cat (still out and making the rounds) plays a lot with the image of 1950s conformity, though I’ve tried not to impose too much of a modern perception on it. As historical novelist Gary Jennings once observed, nobody thinks of themselves as quaint, or old-fashioned and my protagonist’s rather stuffy fashion sense wouldn’t have been that remarkable at the time.
Alternatively, you simply use the era as a backdrop. The Glory That Was (also in circulation) doesn’t really say anything about the 1970s, but it does make use of it as a setting: Watergate, terrorist bombings, the fact 18 year olds could drink. For me it’s important that backdrop stories use enough that nobody reading it thinks “Well, he could have put that in the present and it wouldn’t have made a difference”—I hate it when I watch a movie set in the recent past and don’t see a point to it.
A decade is a lot to capture but that doesn’t mean we can’t give it a shot.