I think with a sound knowledge of Roman history and politics this book would fill in the gaps of these women, who are almost invisible in the records but who ruled different parts of the Roman Empire following the demise of the Egyptian queen Cleopatra VII.
Duane W. Roller, Professor Emeritus of Classics at The Ohio State University, is an ancient historian, archaeologists, and classicist. He is a four-time Fulbright scholar, and the author of numerous scholarly articles and over a a dozen books, including Cleopatra: A Biogragphy (Oxford 2010), Eratosthenes' Geography, and Ancient Geography (London 2015).