Whose flag is this?

THIS island state was annexed by Chile in 1888, but the flag was created in 1880 by the local population when it was planning to have a dialogue with the country about being a modern state.

The red object in the centre is known as a reimiro, which is a wooden pectoral ornament once worn by the local people, and at the edges of the reimiro are two anthropomorphic figures which represent chiefs, or nobles.

Do you know which island’s flag this is?