If you're going to mention 1914 you should note that the original teaching was that the "last days" were from 1799 - 1914. Armageddon was supposed to be a 40 year span of time from 1874 - 1914 and 1914 was supposed to be the start of the Millennium (with no catastrophes then).
Sorry I don't have the citations but it can all be found in Charles Russell 6 book series. The book The Time is at Hand would be the major source of information on that.
As SAHS mentioned, The Gentile Times Reconsidered is the best book on that issue. It is available as a free PDF: https://www.watchtowerlies.com/linked/the-gentile-times-reconsidered.pdf