In 9 A.D., three Roman legions were defeated by the Germanic warlord Arminius at the Battle of the Teutoburg Forest. This event is well-known, but there was another rebellion that Rome faced shortly before, which lasted from 6 to 9 A.D. and was equally intense. This rebellion took place in the western Balkans (in an area roughly corresponding to modern Croatia, Bosnia and Herzegovina, Slovenia, Montenegro, and parts of Serbia and Albania) and tested the Roman Empire to its limits. For three years, fifteen legions fought in the narrow valleys and wooded heights of the Dinaric Alps in a ruthless war of attrition against an equally ruthless and determined enemy. However, this conflict is almost unknown today. The Great Illyrian Revolt is considered the first book dedicated to this forgotten war of the Roman Empire. In its pages, we examine the history and culture of the mysterious Illyrian people, the story of how Rome became involved in this volatile region, and what the Roman army faced during those terrifying three years in the Balkans.