A cinematic climax happens early on in Hollan’s chronicle of the Roman Empire and Caesar’s life: a hush overcomes the Roman troops as “gambler” General Caesar debates crossing the Rubicon to invade Rome, risking life, career and history. The doubt and weight of such a decision, we’re told, is called ‘discrimen.’ The unnaturally talented strategist and leader crosses the river, of course, and the Republic falls. Moments like this are so dramatic, it’s easy to forget this is nonfiction. Keeping track of events of the Roman Empire is almost impossible, and Holland, a BBC radio veteran, is tasked perfectly with making it digestible. The book is a fascinating, high-impact account of war, catastrophe and change.