Commons:Copyright rules by territory/Northern Mariana Islands
The Northern Mariana Islands is an insular area and commonwealth of the United States consisting of 14 islands in the northwestern Pacific Ocean. It includes the 14 northernmost islands in the Mariana Archipelago. It does not include the southernmost island of the chain, Guam, which is a separate U.S. territory.
Spain made the islands part of the Spanish East Indies in 1565. In 1899 Spain ceded Guam to the United States and sold the Northern Marianas to Germany. During World War I Japan invaded the islands, and in 1919 they became part of Japan's South Pacific Mandate. After World War II the United States took over administration as part of the United Nations Trust Territory of the Pacific Islands. A new government and constitution came into effect in 1978 under when the islands obtained commonwealth status within the United States.
Presumably the United States federal copyright laws apply.