How to handle large amounts of authors

I’m in the process of migrating an old site with thousands of articles. The site was originally a magazine dating back to the sixties. There are hundreds of authors.

I’d like to have proper authorship displayed when reading the articles and author pages for lists of articles written In Ghost this seems to be the (staff) user. I can’t find a way to create these users through the API. It’s of course impossible to use the invite function.

Is there another way to handle this situation?