Christianity was perverse long before the Popes got ahold of it.
Mr. Starkey first posits a true thesis in describing Islam as a religion of conquest and then demonstrates that being an expert in one field of history (Elizabethan England) does not imply expertise in another area of history where he, indeed, demonstrates profound ignorance (The Crusades). The Crusades were, in fact, a Christian RESPONSE to the very Islamic conquest of lands which had been Christian for centuries. The first crusades, far from being an attempt to EXPAND the influence of Christendom were merely a defensive measure AGAINST Muslim military expansionism. Mr. Starkey should spend some time studying the works of historians Jonathan Riley-Smith and Thomas F. Madden (who ARE experts on the Crusades) before he makes further uninformed utterances on the subject.