This book is the first coherent quantified assessment of the economy of the Roman Empire. George Maher argues inventively and rigorously for a much higher level of growth and prosperity than has hitherto been imagined, and also explains why, nonetheless, the Roman Empire did not achieve the transition which began in Georgian Britain. This book will have an enormous impact on Roman history and be required reading for all teachers and students in the field. It will also interest and provoke historians of the medieval and early modern periods into wondering why their economies failed to match the Roman level. Part of the problem in assessing the Roman economy is that we do not have much in the way of numerical data, but Roman historians, who rarely have much statistical expertise, have not always recognised the potential of the data we do have. Dr Maher's reassessment of the economy of the Roman Empire has to use the same data as everyone else, but he is able to draw strikingly novel conclusions in two ways: first, by more statistically sophisticated use of a few crucial datasets and, second, by correlating and drawing a coherent picture across the whole economy. On grain yields, firstly, instead of getting bogged down in details of individual cases, George Maher shows how there is a remarkably consistent pattern from which outliers can be excluded, showing yields were much higher than normally assumed. He then demonstrates that high yields are in fact necessary to explain the exceptional urbanization of the Empire. Urbanization at this level in turn, as George Maher shows, has implications for consumption and commerce. He takes this further to show how high levels of trade imply high levels of sophistication in economic practices and mentality. In one of his most methodologically novel chapters, George Maher develops a new and simpler way of assessing average life expectancy and argues for a life expectancy almost double the traditional view. This book, Dr George Maher's doctoral thesis, is the theoretical underpinning of his book Pugnare: Economic Success and Failure.