This may be <a href="https://www.geni.com/people/Theobald-von-Zastrow/57864">Theobald Maximilian Theodor von Zastrow (1896-1983)</a>, the name of Theobald (or Theobold) for the author could be verified via <i>First Over the Front</i> by Stan Walsh and William G. Schauffler (the same one from G-8 and His Battle Aces fame). Baron von Zastrow lived in the USA after WW1.