Teppoki (Gun Chronicle) is a history book concerning the transmission of guns to Japan, and was completed in 1606 during the Edo period. The book is based on the account given by Hisatoki TANEGASHIMA, a local lord, concerning the historical fact of the transmission of guns (specifically, arquebuses) to Japan on Tanegashima island during the Sengoku Period (Period of Warring States), describing how Hisatoki's father Tokitaka TANEGASHIMA had acquired guns and established his gun manufacturing process; this account was edited by the abbot of Satsuma Province's Dairyu-ji Temple, Bunshi Nanpo.
Another theory, advanced by Takehisa UDAGAWA and others, holds that before the arrival of guns in Japan, primitive firearms had already been introduced into by wako (Japanese pirates) and other people, but the "Teppoki" provides an account of how firearms (arquebuses) were brought to Tanegashima Island in 1543 by Portuguese sailors ("introduction of guns into Japan"). Both because the description given in the "Teppoki" is very detailed and because no other historical record describing the transmission of guns on Tanegashima island exists, the Teppoki is used as the source document for the transmission theory.
The book was completed 27 years after Tokitada's death and almost 60 years after the transmission of guns itself. The chronicle was compiled by the sixteenth family head Hisatoki to honor his father Tokitada TANEGASHIMA.