In preparing this talk, I had a choice, to look at topics or people.

The way individual topics (for example, quadratic reciprocity, Pythagoras' Theorem or such giant topics as geometry) cover history is not very consistent. These tend to be large articles with lots of authors, and very diffuse. In truth, keeping track of the history of important topics is very complex, and I don't think Wikipedia will ever handle it well. Among other things, the Wikipedia pages on important topics tend to attract people with obsessions.

So I chose to consider pages on individual mathematicians. In principle, this is more interesting way to cover history. Digestible in small bites. Easier to organize. Limited responsibility for authors, and less unwanted interference.

I shall look only at the entries of a small and haphazard selection of mathematicians with whom I am familiar. I believe that for my purposes they are a good sample.