This tale is set in medieval Japan during the Kamakura Period (1185-1333).Primary sources include "A story of Oki Islands" in Ancient Tales and Folklore of Japan (1908) by Richard Gordon-Smith,and an adaptation published as "The Slaughter of the Sea Serpent" in Myths and Legends of Japan (1912) by F.Hadland Davis.In his introduction to the earlier work Gordon-Smith comments:"The stories in this volume are transcribed from voluminous illustrated diaries which have been kept by me for some twenty years spent in travel and in sport in many lands-the last nine of them almost entirely in Japan,while collecting subjects of natural history for the British Museum (and) trawling and dredging in the Island Sea (site of the Oki Islands)." A variety of collateral sources provided insight into the history and culture of the period;the geography of Shima province on Japan`s west coast and situacion of the Oki Islands;matters political,military,and religious;and the remarkable feast of the diving women,whose time-honored occupation continues to draw great numbers of tourists to Shima province.