Nihon Shoki

, also known as the , is an early book about the history of Japan up to 720 A.D. It is one of the national history books which are together called the "Rikkokushi".
History.
"Nihon Shoki" is the second oldest book of classical Japanese mythology and history. It includes details that are not in the "Kojiki", which is the oldest historical record of ancient Japan.
This book is important to people who study the history of Japan because it has information about the early rulers not found in other books.
Dates in the "Nihon Shoki" before the late 7th century were likely recorded using the Genka calendar system.