For a single file you can use `git log` to show you all patches that changed the file, going back in history forever:

  git log --follow --patch -- some/file

It composes with Tomte's @{1 year ago} tip if you want to start reading at a particular point in time:

  git log --follow --patch 'main@{1 year ago}' -- some/file

ref: https://git-scm.com/docs/git-log