For thousands of years, Hat Island (known as č̓əč̓əsəliʔ in the Lushootseed language)[3] was the site of a village of the Snohomish people.

[4] Hat Island was first mentioned in the historical record by naturalist Archibald Menzies of the Vancouver Expedition in 1792.

[5][self-published source] In the 1820s, a large landslide at Camano Head created a tidal wave which crashed into Hat Island.

From that point on, the island was only used by the Snohomish as a temporary camping ground when clamming, never as a permanent living site.

People who returned occasionally found human remains or parts of the destroyed village.