Nero fiddled while Rome burned. As catchy as that aphorism is, it’s sadly untrue, even if it has a nice ring to it. The one thing Nero is well-known for is the one thing he actually didn’t do. But fear not, the truth of his life, his rule and what he did with unrestrained power, is plenty weird, salacious and horrifying.

And he is not alone. Roman history, from the very foundation of the city, is replete with people and stories that shock our modern sensibilities. Evil Roman Emperors puts the worst of Rome’s rulers in one place and offers a review of their lives and a historical context for what made them into what they became. It concludes by ranking them, counting down to the worst ruler in Rome’s long history.

Lucius Tarquinius Suburbus called peace conferences with warring states, only to slaughter foreign leaders; Commodus sold offices of the empire to the highest bidder; Caligula demanded to be worshipped as a god, and marched troops all the way to the ocean simply to collect seashells as “proof” of their conquest; even the Roman Senate itself was made up of oppressors, exploiters, and murderers of all stripes. Author Phillip Barlag profiles a host of evil Roman rulers across the history of their empire, along with the faceless governing bodies that condoned and even carried out heinous acts.

Roman history, deviant or otherwise, is a subject of endless fascination. What’s never been done before is to look at the worst of the worst at the same time, comparing them side by side, and ranking them against one another. Until now.

Phillip Barlag is an Executive Director at World 50, a Morgan Stanley company which initiates and facilitates the most interesting and influential business conversations in the world. He is the author of The History of Rome in 12 Buildings and the acclaimed The Leadership Genius of Julius Caesar, and his writing has been published in Fast Company, MIT Sloan Management Review, and ChangeThis.com, among others. He lives in the Atlanta, GA, area with his wife and three children.