From the cover -
"The deep forests of Hârn are home to eighteen tribal nations. The homeland of each tribal nation is indicated on the Tribal Nations map.
"Although civilized Hârnians look down on them as backward, most tribesmen have more freedom and leisure time than manorial peasants. However, much of that spare time must be spent sharpening spears and fletching arrows because the tribal wilderness is a more dangerous place than the manor.
"Barbarians: An overview of tribal culture, economics and religion. A guide to character generation for tribal characters is also included.
"Tribal Nations: A separate 4-6 page article for each of the eighteen tribal nations. Each article includes a tribal map, occupations, weapons and armor, history, culture and specific shaman rituals."