period. Jomon beliefs in natural spirits are theorized to have given rise to Ainu spirituality. About 2,000 years ago, the island was colonized by Yayoi people, and much of the island's population shifted away from hunting and gathering towards agriculture.

The Ebetsu Kofun Cluster is a group of mounds dating from the latter half of the 8th century to the middle of the 9th century, and was surveyed by Juichi Goto in 1931. Along with the kofun,