It was created in June 2006 with 140,000 square miles (360,000 km2) and expanded in August 2016 by moving its border to the limit of the exclusive economic zone,[1] making it one of the world's largest protected areas.

It is internationally known for its cultural and natural values as follows: The area has deep cosmological and traditional significance for living Native Hawaiian culture, as an ancestral environment, as an embodiment of the Hawaiian concept of kinship between people and the natural world, and as the place where it is believed that life originates and to where the spirits return after death.

Much of the monument is made up of pelagic and deepwater habitats, with notable features such as seamounts and submerged banks, extensive coral reefs and lagoons.

[5] The National Marine Fisheries Service (NMFS) reported in 2008 that many species’ populations have not fully recovered from a large-scale shift in the oceanic ecosystem that affected the North Pacific during the late 1980s and early 1990s.

About 132,000 square miles (340,000 km2) of the monument are part of the Northwestern Hawaiian Islands Coral Reef Ecosystem Reserve, designated in 2000.

[13][14] President Bill Clinton established the Northwestern Hawaiian Islands Coral Reef Ecosystem Reserve on December 4, 2000, with Executive Order 13178.

[15] In April 2006, President George W. Bush and his wife viewed a screening of the documentary film Voyage to Kure at the White House along with its director, Jean-Michel Cousteau.

[16][17][18] On June 15, 2006, Bush signed Proclamation 8031, designating the waters of the Northwestern Hawaiian Islands a national monument under the 1906 Antiquities Act.

Using the Antiquities Act bypassed the normal year of consultations and halted the public input process and came just before the draft environmental impact statement for the proposed Northwestern Hawaiian Islands National Marine Sanctuary was to be published.

This was the second use by Bush of the Antiquities Act, following the declaration of the African Burial Ground National Monument on Manhattan in February 2006.

[24][25] Frank McCoy, then chair of the Western Pacific Regional Fishery Management Council, claimed: We are pleased the President recognizes the near pristine condition of the Northwestern Hawaiian Islands waters.

[citation needed] In August 2016, President Barack Obama expanded the monument's area by roughly four times, to the limits of the exclusive economic zone.

[38][39] On October 21, 2019, the wreck of the Imperial Japanese Navy aircraft carrier Akagi, which sank during World War II in the Battle of Midway on June 4, 1942, was found within the monument by the research vessel Petrel.