I have added a file into TFVC. Subsequently I have found a previous incarnation of the same file which is a predecessor to the one currently version controlled.
I would like to have this found file in the history as a previous version.
Can I insert this previous version into the file's history somehow?
As there is currently only one commit on this file, would it be easier just to delete the thing and start again, committing the found one as the first version?
No, you can't change the history. Since there is currently only one commit on the new added file, you may consider manually updating the original file with the new changes and abandon the new added file.