The late historian Dr. Robert Darby, PhD wrote a great deal on this topic. Here are some of his published works you can consult:

The masturbation taboo and the rise of routine male circumcision: A review of the historiography. Journal of Social History, 2003.

The riddle of the sands: Circumcision, history, and myth. New Zealand Medical Journal, 2005. You can read the article by scrolling down the page if you don't want to download it.