Why did some early Fijian settlements build ridge forts and ring-ditch fortifications?

In early Fijian society, the construction of defensive structures was a response to the prevalence of warfare.1

• Ridge forts were typically associated with small communities that practiced slash-and-burn agriculture.1
• Ring-ditch fortifications were utilized to protect larger, densely populated settlements located in fertile delta regions, such as those in southeast Viti Levu, where inhabitants relied on intensive taro cultivation and complex irrigation systems.1

Traditional Fijian society was hierarchical and organized through kinship and residence, often leading to a flexible network of alliances that could shift between cooperation and conflict. Because warfare was common, these fortifications served as essential protection for communities against potential conquest or raids by rival groups.1