For those who don't know, the Emperor Valens was the man who lost the Battle of Adrianople to the Goths thus allowing them to establish themselves on Roman territory. They never left it for the rest of the history of Rome. Many historians see this as the battle that led to the end of Rome 98 years later. So essentially Valens is remembered as a great failure. If you're wondering why someone would want to read a book on a failure then the author has an answer for you. The book is designed to show what qualities were needed in an emperor by showing the qualities that Valens had and the ones he was lacking. And Valens did have good qualities. He wasn't one of those despotic tyrants that show up from time to time in Roman history. He was just a man of average abilities who found himself unable to cope with events. He's also well documented for a fourth century emperor. Ammianus Marcelinus describes his as consisting of "equal parts good and bad qualities," which is another advantage to a historian. The man is not obscured by propaganda in this era of high religious tensions. Nobody tries to make him a saint or a villain, he's just... a man.
OK, onto the book. Aside from the kudos due to the choice of such an awesome topic, there are many reasons to read this book. As far as I know, there aren't any other biographies of Valens out there so you're pretty much stuck with this one anyways. But that's OK, because this book is all you'll need. As mentioned above the book's main purpose is to analyze Valens' abilities and find out what he had and what was lacking. The information on this is fascinating, but it's also arranged in chronological order which means that it reads like a biography and not just some scholarly thesis. The book is written very well on the whole. It maintains your interest all the way through. It also includes probably the most in-depth analysis of the Battle of Adrianople to be found anywhere. Another good reason to check this out. This is one of those books where you really feel an understanding for this era. The world comes to life, as does Valens in all his glory/infamy.
Now, the downside. First and most obvious is the price. This book goes for about $80. If you see it for under $40 grab it! It'll be worth it. For those of us who have no money, there is another excellent book on the battle of Adrianople called The Day of the Barbarians. It's a short book but it covers the battle almost as well as this one and for a fraction of the price. It doesn't include more than a minimal sketch of Valens but that's the price you have to pay for cheapness I suppose. The only other problem is the author's tone. It never gets in the way of the story, but the author's tone tends to be really cocky. Ridiculously so at times. Again, it isn't enough to interfere with the story but it can get on your nerves. Fortunately, most of that comes in the Introduction and the Conclusion. In conclusion I can recommend this book VERY strongly, but due to price considerations it's probably a rental and not a buy. If money is no object to you then I'd say buy it, and could you possibly talk to me about my college loans Rich Boy?