This is a massive study of the Roman Legions. The author covers all aspects, enlistment,pay, training, officers, organization, training, camp life etc. He then goes on to describe the history of each legion, and also the Praetorian Guard, the Equites Singularies etc.. The author is not afraid to take on theories long held by many historians on Legionary origins, such as Mommsen's opinion that Legion 10 Fretensis is not Caesar's famous 10th Legion, the author believes Mommsen is wrong and that it is indeed Caesar's 10th. He also has what is sure to be controversial ideas on Legionary shield emblems, that certainly don't match ideas long held by other historians. Ditto Trajan's Column, the author belives that historians have been mislead by what is on the column as to shield emblems and other aspects of Legion equipment. The last part of the book is an in depth study of the battles that the Legions took part in, it is an excellent military history of the Roman Legions. The book is excellent, and will surely spark a new look at the Roman Legions by historians.