I have a couple of repositories in GitHub but before I created them there they existed for 20 years as local copies on my local drives. I have taken regular backups over the years and would like to know if I can import them to GitHub somehow to give a history for the repositories and allow diffs? The files have not existed in any version control other than as files in a filesystem, though I do have the backups all nicely organised and dated with comments. Locally I use GitHub Desktop and also have Mercurial and SourceTree
I did wonder about simply pushing them to GitHub one by one, overwriting the local copy sequentially moving forwards in time - perhaps not all 20 years, but significant points. I am not sure how this will leave me in terms of dates and versions?
I have a feeling that what I want to do may not be possible but if anybody thinks it is could they please point me in the right direction via an article, search term or anything really