You may select any link on the History Page to review a document that you have previously visited. That link, and any subsequent to it, will not be removed from the history stack if you return to it via the History Page. You thus should use a History Page link, rather than the left-arrow key, if you wish to review previous documents without needing to remember and repeat the series of selections for reaching your currently displayed document.
Upon using left-arrow in the document selected via the History Page, you will be returned to the document from which you initially went to the History Page.