Reddit mentions of 19th-Century Fashion in Detail

There are a lot of great suggestions here already, but I'd like to add fashion books. I'm talking like those big coffee table books on historical fashion or specific designers. Stuff like 19th Centry Fashion in Detail or Alexander McQueen: Savage Beauty. They can get a little pricey but I've found that there's a fair selection of those sorts of books at my local library.

For inspiration on trends, I like to go to fast fashion websites (large inventory, often refreshed) that do more full-outfit styling on their stock photos like ASOS and see what sorts of elements are recurring and how I feel about the styling.

As many people have mentioned already, Pinterest isn't great for up-to-date trend inspiration but I like to use it for more mood-based or non-fashion-based inspiration like botanical inspired fashion. I recommend keeping an entirely separate pinterest account for fashion stuff and using it frequently to get better recommendations. I also make sure to add my own pins to boards periodically from shop photos or instagram and that seems to help with getting more recent-looking pins.

For direct outfit inspiration on instagram I mostly just follow the #redditffa tag. I've yet to find any larger tags that are not completely polluted with referral links and shops.