If you restore the page, all revisions will be restored to the history. If a new page with the same name has been created since the deletion, the restored revisions will appear in the prior history.
MediaWiki:Undeletehistory
From Layton Support
If you restore the page, all revisions will be restored to the history. If a new page with the same name has been created since the deletion, the restored revisions will appear in the prior history.
