Hawaii Island

Hawaii Island, frequently called the Big Island, is the largest and southeasternmost island of the Hawaiian archipelago and forms part of the State of Hawaii in the United States. It accounts for approximately 63 per cent of the total landmass of the archipelago, yet it contains only around 13 per cent of its population. With its vast volcanic landscapes, significant cultural traditions and substantial geological activity, the island holds an important position within both Polynesia and the wider Pacific region.

Names and Administrative Context

To distinguish it from the state, the island is commonly referred to as Hawaii Island or the Island of Hawaii. The epithet Big Island reflects its size relative to the other Hawaiian islands. In Hawaiian, it is traditionally known as Moku o Keawe, a name carrying several meanings. One interpretation links Keawe to “the Southern Cross”, believed to be associated with an ancient chief; another defines it as “the bearer”.
Hawaii County, covering the entire island, is the relevant administrative authority. As of the 2020 United States census, the county population was 200,629, with Hilo serving as its seat and largest settlement. The county operates without any incorporated municipalities.

Historical Background

The island’s name is traditionally attributed either to Hawai‘iloa, a legendary Polynesian navigator reputed to have discovered the archipelago, or to Hawaiki, a mythical homeland in Polynesian tradition. Early European accounts often recorded the name as Owyhee or Owhyhee.
Archaeological evidence suggests that Polynesian explorers from the Marquesas or Society Islands may have arrived in the region between 900 and 1200 CE, with earlier theories placing arrival as early as the 3rd century CE. Subsequent waves of migration may have come from Tahiti, shaping the cultural and linguistic landscape of the islands.
Oral history identifies ‘Umi-a-Līloa as one of Hawaii’s most notable ali‘i nui (high chiefs). A son of Līloa, he came to power by defeating his half-brother Hākau and later consolidated control of districts across the island. His rule established Kailua-Kona as a seat of governance.
European contact was established in 1779 during Captain James Cook’s third Pacific voyage. The islanders initially received Cook as an incarnation of the god Lono. After departing and then returning due to storm damage, a violent confrontation on his second arrival resulted in Cook’s death. Relations between the Hawaiians and the surviving crew were subsequently restored.
Later in the eighteenth century the island was ruled by Chief Kalani‘ōpu‘u, who on his death in 1782 left succession disputes that precipitated civil conflict. Kamehameha I, Kalani‘ōpu‘u’s nephew, eventually emerged as the dominant figure, defeating rival chiefs including Keōua and Keawema‘uhili. By 1810, through both warfare and diplomacy, he unified the Hawaiian Islands under the Kingdom of Hawaii, named after his home island.
Missionaries such as William Ellis visited in the early nineteenth century, documenting island communities and landscapes. In 1898 the Hawaiian Islands were annexed by the United States, becoming the Territory of Hawaii, and in 1905 the County Act formally established Hawaii County.

Geography and Geological Setting

Hawaii Island covers the largest land area of any county in the United States, constituting more than 62 per cent of Hawaii’s total land area. The island spans considerable distances, reaching its widest extent across substantial volcanic slopes. At its tallest point, Mauna Kea rises more than 4,200 metres above sea level and, when measured from its submarine base, is considered the tallest mountain on Earth.
The island’s southernmost point, Ka Lae, marks the southern extreme of the United States. To the northwest lies Maui, separated by the Alenuihāhā Channel, from where the volcanic summit of Haleakalā is visible.

Volcanism and Geological Development

Hawaii Island is composed of five shield volcanoes, which formed sequentially and now coalesce to create the island’s present landmass. These are, from oldest to youngest:

• Kohala – extinct
• Mauna Kea – dormant
• Hualālai – active
• Mauna Loa – active
• Kīlauea – active

Mauna Loa and Kīlauea, both within or partly within Hawaii Volcanoes National Park, remain among the most active volcanoes in the world. Geological evidence from ancient surfaces once suggested that the now-buried Nīnole and Kulani structures were separate volcanoes, although they are now considered older parts of Mauna Loa.
Distinct geochemical signatures divide Hawaii’s volcanoes into two magma-system “families”: Hualālai–Mauna Loa and Kohala–Mauna Kea–Kīlauea, indicating discrete mantle sources.
The island continues to grow because of ongoing volcanic activity. Between 1983 and 2002, eruptive events added new coastal land. Lava flows destroyed communities including Kapoho, Kalapana and Kaimū, and in 1987 filled the notable freshwater pool known as Queen’s Bath. The 2018 lower Puna eruption, particularly from Fissure 8, added hundreds of hectares of new land and covered features such as Green Lake and sections of Isaac Hale Beach Park.
Mauna Loa resumed eruptive activity briefly in 2022 after nearly four decades of inactivity.
Geologists also identify two submarine volcanoes associated with the island’s base:

• Māhukona – an eroded, now-submerged edifice northwest of the island
• Kama‘ehuakanaloa Seamount (formerly Lō‘ihi) – an active submarine volcano southeast of Hawaii Island