This book was written to confirm Korea’s territorial right over Dokdo. Dokdo is clearly Korean land that rightfully belongs to the Korean people historically and by international law. However, the government and scholars of Japan claim the island as Japanese territory. The Japanese government has attempted to make Dokdo a subject of “legal dispute,” mounting a proposal to take the matter to the International Court of Justice. This book was written in this context to confirm Korea’s territorial right over Dokdo. The book comprises seven chapters. Chapter 1 introduces Dokdo’s history, geography, and ecosystem. Chapter 2 surveys Korea’s official records of Dokdo, from the History of the Three Kingdoms (K. Samguk sagi) and Memorabilia of the Three Kingdoms (K. Samguk yusa) to the Annals of King Seongjong (K. Seongjong sillok), to uncover perceptions of Dokdo found therein. Chapter 3 examines An Yong-bok’s confrontation with Japan as recorded in the Annals of King Sukjong (K. Sukjong sillok), explaining how Dokdo was already perceived as Korean territory at the time. Chapter 4 investigates the Meiji government records that acknowledged Korea’s territorial right over Dokdo and Ulleungdo. Chapter 5 retraces the Joseon government’s incorporation of Dokdo into Ulleung-gun County, which was followed by the Japanese government’s illegal incorporation of the island in Shimane Prefecture. Chapter 6 sheds light on the restoration of Dokdo to Korea following Japan’s defeat in WWII. Chapter 7 analyzes how, upon regaining its sovereignty, Japan has attempted to make Dokdo a subject of “legal dispute.”