According to a fact that Jomon-style earthenwares (straw-rope pattern potteries) were excavated from Kosagishima, it seems that the ancient people lived in the island from B.C.
Also other earthenwares for producing salt from seawater were found, and probably they were made before the Nara period. In the Edo period, new style pans were made.
In the period of warring states, a military commander built a shrine in this island as an important base.
Time passed to the present. There were approximately 3000 islanders, but the population gradually decreased after 1955. And Sagishima is aging like other islands in Japan.
The islanders, however, are more active in such the situation. They have held triathlon race since 1990. In addition, they guide tourists around the island, and introduce the fascinations of Sagishima.
The history of Sagishima would be kept by the islanders from now on.