I think this can cover for a lot of people's reasons for why we're here.

In all seriousness, everyone has their own separate story on how they stumbled upon AskHistorians and got around to contributing. I remember AH answers showing up on google searches for questions I had looking for answers on Quora around 5-6 years ago. I took a look, found answers I was looking for, and kept the sub bookmarked to browse in my spare time. I was a recent graduate with a bachelors in History and thought I would try my hand at answering questions on my own...to mixed results. I didn't fully understand the rules or just how deep they wanted me to dig in order to produce an answer that was up to snuff, and it was about 50/50 on my answers staying up or were removed. I read the resources listed in the sidebars, the rules roundtables which are peppered all in the general rules, and this most important one (to me), what makes a good answer.

I deleted my old account that was more centered on memes and other shitposts and made this to be more AskHistorians centered and started building a resume of sorts from scratch, and here I am. Though looking back between my first answer on this account and a more recent answer, man the amount of self-improvement is astounding, brought on by the standards sought by this platform and the resources AH has out there to help people write that wall of text we all enjoy reading!

As for how to attract people to contribute, people stumble upon here however they may and contribute answers themselves, and the community (moderators) picks up on people who start to establish a track record of quality answers. There's a shortlist out there of people who have consistently put out good stuff as candidates for flair, and those will likely get a message from a moderator encouraging them to apply for flair, the sweet, sweet coveted text box saying you know a thing.

The moderation team also puts together methods of engagement through a variety of methods. Flairs or special guests may be invited to do an AMA on a certain topic, especially if talk about a certain historical period picks up due to a recent movie release, book release, etc. There's podcasts with flairs or other special guests brought on to talk. There's also the digital conference with flairs and guests that started just last year, and much more.

For people who know a thing and feel like they want to contribute, please don't feel afraid to contribute, as long as you know the standards of the subreddit and feel you have the expertise to answer both the question and follow up with more information if/when asked. Best rule of thumb I can give to those wanting to contribute is to read the good answers that are everywhere on the sub, the weekly Sunday digest is an excellent recap of posts from the last week as a place to start, take note of the amount of detail they go into, what's addressed/covered, and use already existing answers as a template for your own work. I'm not ashamed to admit I used other flairs' answers as a template to write with. And if you feel like you want someone to review answers or want some coaching, many flairs and some mods are completely up for helping you out!, here's a list of flaired profiles, with most having a note on whether it's cool to message them. If anyone wants an answer related to 19-20th Century Italian history reviewed, I'll personally be open to talk!

^^^^More ^^^^can ^^^^be ^^^^said, ^^^^but We had a thread on a similar subject earlier this year you may be interested in: About how long ago did this sub start becoming heavily moderated? It features nostalgic reminiscing of the subreddit's journey, links to older announcements across the shift, stories and thoughts from the mods, and more. There used to be a page on the website outlining the history, but I can't find it now, but most of that information should be find in that aforementioned thread or the ones it links to.

For what AH might demonstrate about internet communities in general, you may be interested in the work of /u/SarahAGilbert, one of the mods, who has studied and written about the nature of moderating a forum like AskHistorians on a website like Reddit—here is a published paper on the subject and an accompanying thread.

Could it work for a field like public policy? It's not at quite the same level, but /r/NeutralPolitics does have similar moderation tactics, in making sure that everything people write is informative, researched, and contributing to discussion.

As always, though, there's plenty of room for further discussion, if people have more to add.

The fact of the matter is that most historians write for an audience of other historians. Usually also for other historians of a narrow specialty area, too. This keeps quality very high but limits overall dissemination heavily.

I imagine the opportunity to summarise things that you already know a lot about for a much wider audience that it may otherwise never reach is pretty appealing for many.

Others have answered your big question from their perspective, but with this one:

I'm also by extension asking if there are lessons to be learnt for creating other communities that value the voices of subject matter experts. Is reddits upvote system serviceable? Do you have another system you think would be better at promoting "correct" answers?

Generally, Reddit's upvotes system is a tool, and like any other tool, it has positives and negatives (...some we'd upvote, some we'd downvote?)

As moderators we honestly have very little control over which questions people upvote, beyond our choices of what to approve and remove. If it were otherwise, some of the things we want to push - AMAs, other special features - would get many more upvotes!

The advantage of the upvotes is that it means that people get to see questions about history that are likely to interest them; the problem with this is that /r/AskHistorians has a particular demographic fairly typical of much of Reddit, and it has blindspots as a result in terms of what it finds interesting (so some people find it much harder to find things on AskHistorians that interest them). As a serious history subreddit, we're competing against cute pictures of cats, memes about pop culture, and political discussion in peoples' Reddit feeds, and so what gets upvoted can be prurient and shallow, or can be a surprisingly good question that historians have largely ignored - it sometimes depends on who is browsing Reddit on their phones that particular time of day and what they happen to be interested in. We have our 'Great Question!' flair to try and promote questions that make us jaded mods go 'oh, that's an interesting one!'

In terms of upvotes promoting 'correct' answers (rather than good questions), I think generally the people who browse our subreddit have a relatively good idea of what is obviously not anywhere near close to an AskHistorians quality answer, and downvote it according. But after a certain point, we do find that answers that aren't up to our standards do get upvoted fairly heavily before they get removed. Upvotes, for us, don't really seem able to distinguish between good and bad answers beyond a certain poitn.

There are a few reasons for this: 1) people like to see an answer, and assume that if they see one and we've not yet removed it, it must be good; 2) people reading the subreddit don't always have the historiographical knowledge etc to tell the difference between a properly sourced answer by an expert and something cobbled together after half-hearted googling; 3) people forget this is r/AskHistorians, and upvote things without caring as much for quality as the moderation team does. In situations where these kind of '40% good answers' get upvoted, we definitely notice that the excellent answers languish underneath not getting the upvotes they deserve (or the flairs who could have answered decide 'ah, I can't be bothered, nobody will see it' and don't try, where if there was no answer, they might.

Bonus question in regards to the 20 year rule. This rule helps the forum sidestep a lot of questions that are quite political in nature (which is great). But would r/AskHistorians model work for a subreddit on e.g. Public Policy? Do you think such a topic would require very different forum rules?

I think on a subreddit about Public Policy, you can't have a 20 year rule - public policy has to be about how things are now, not how they were over 20 years ago. But I get the impression that equivalent subreddits have equivalent ways of avoiding or corralling topics that everybody is tired of, or that don't fit well onto their subreddit. I get the impression that /r/AskPhilosophy got very sick of questions about Jordan Peterson from fanboys who are not always happy to discover that actual philosophers are unimpressed by Peterson in various ways, and so they have rules about that kind of thing. The same would go for a subreddit about public policy, I imagine, except with whatever prominent YouTuber posts uninformed things about that particular topic area, rather than Peterson.

But at some level, a subreddit that is aiming to provide a place where people with expertise can expound upon what they know, you want to make it an inviting environment for them - one where they're not harrassed, and where they feel their volunteering to write something good is going to be appreciated rather than largely ignored. So having some sort of expectation of what expertise looks like and how it will be appreciated in the subreddit can definitely help. Subreddits like /r/musictheory and /r/askbiblicalscholars require flaired users to show mods their diplomas to prove they have expertise - in contrast we don't need to know whether our flairs have PhDs, but we do have a set of standards of what a good answer looks like that is easier to achieve if you have expertise, whether through formal or informal learning.

A 20 year rule on a Public Policy form sounds an awful lot like you'd want people to discuss things like the first round of Bush tax cuts or the 2001 Labour General Election Manifesto at the absolute newest. It either sounds like political history-by-another-name or a very obsolete forum for public policy debate.

I'm not someone who came up with the 20 year rule, nor is it a universal thing (or shouldn't be, anyway, there is history newer than that), but my understanding as to why that rule exists is to keep an online forum from getting inundated with contemporary politics debates, plus a holding action to avoid all need to discuss 9/11 and related conspiracies until this year.

Not a historian, BUT...

...but I can answer:

A small, yet well-organized, group of people decided that they could use this sub to push forward their own specific narrative and version of history, as long as they could make it so that they could prevent the "wrong" questions from getting asked, or the "wrong" answers from being given.

Thus, a moderation coup was orchestrated, removing the old, more loose, yet well-meaning leadership, with the new, stricter and agenda-driven one.