A fascinating bit of history well covered in this book, but sadly let down by an overly familiar style and unnecessarily complex sentence structures. I must have read some sentences three times or more before I understood what was meant. I don't have that problem with most other books so an Anthony Beevor or Andrew Roberts Tom Holland is definitely not. Pity, as the research is epic.
The subtitle is Battle for Global Empire and the End of the Ancient World. The empires are not just those of the Romans, Sassanids and Arabs, but also Christian, Zoroastrian, Jewish and Islamic faiths. I am sure some of the books observations would give many of the believers conniptions.
Mark B lent me this book because of my interest in Byzantine, an era of history I am not very familiar with. So this book helped set the big scene, and a lot more.