For photos of the way we were /r/TheWayWeWere

For photos of major historical events and historically notable people: /r/HistoryPorn

For colorized photos (historically notable and otherwise): /r/ColorizedHistory and /r/Colorization

For more early photography, with a focus on early camera technology: /r/earlyphotography

For a sampling of the suave and debonair ladies and gents of yesteryear: /r/oldschoolcool and /r/retroparents. For the more sultry side: /r/vgb (may be nsfw)

For the stranger side of life: /r/OldSchoolRidiculous

For Black History: /r/BlackHistoryPhotos

For pictures of extant buildings while they were being constructed: /r/HalfbuiltHistory

For time-specific pictures: /r/VictorianEra, /r/1920s, /r/1950s, /r/1960s, /r/1970s

For vintage advertising: /r/vintageads

For newsreel videos: /r/NewsReels

For our more-recent past: /r/vintage and /r/vintageads