I don't have much experience with "history of math" questions or the ho.history-overview tag. I tried to distill an answer to my question from looking at existing questions, but failed to find the pattern. Here are a few partial answers:
- If the question is about the history of a mathematical definition or concept, with a concrete answer, like "who was the first to do X?" then it seems to be non-CW. Example. Example2
- If the question is going to elicit a big list, or have answers that are primarily opinions (so that votes represent agreement/disagreement with the opinions being given) then it seems it should be CW. Example. But even this is not a hard-and-fast rule. Here's an example where the OP writes "I would like to see a longer such list!" suggesting that he wants a "big list" but the question is still not CW.
Then there are cases where I see conflicting evidence and so I don't know the standard.
If the question is about math-adjacent history but not about math research/concepts/definitions etc, then it seems to stay open if and only if the community finds it interesting. I can't find any consensus about whether or not it should be CW. Example where it's not CW. Another example not CW. Another example not CW (but barely survived closing). An example where it was made CW by moderators. And lastly, an example where it was closed.
Hence my questions:
(1) When, precisely, should a history question be closed?
In the examples above, I see an increasing trend towards trying to send the question to the History of Science and Mathematics Stackexchange. But, I can't find a thread on meta where the consensus of the community (by answers or by voting patterns) suggested that we want to send all history questions away.
(2) When should a history question be CW?
It's interesting to note that a question can be closed and still not CW, so still generate reputation gain/loss for the OP and answers. So, I think it's worth it to answer both questions.