The man who unified the Hawaiian islands under one Chief began his conquests on the island of Hawai’i. Heading into Kamehameha Day weekend, let’s take a look at how Kilauea’s explosive eruption in 1790 may have advanced Kamehameha’s cause. HPR’s Noe Tanigawa reports.

An overview of the footprints embedded in the Ka'u desert lava fields.

Hawai'i Volcanoes National Park Archaeologist Jadelyn Moniz-Nakamura discusses footprints left by Keoua's army and others, as well as other archaeological features in the park.

On Hawai’i Island’s lava flows to the southwest of Kilauea crater, in the middle of the Ka’u desert, you find shrubs and tall grass growing out of the black pahoehoe. Look a little closer, and human footprints appear, embedded in the lava field.

Hawai’i Island in 1790 was a battlefield chessboard with chiefs pitted against each other for dominance, according to Kamakau. Kamehameha and Keōua Kūʻahuʻula were cousins whose armies had engaged in bloody battles from Kohala to the Hamakua coast. Exhausted, they paused, with Keoua’s armies heading home to Ka’u through Ola’a and the Kilauea caldera area.

In his book, Ruling Chiefs of Hawai’i, eminent historian, Samuel Kamakau writes about a fateful day in November, 1790:

"This is how it happened: A pillar of sand and rock rose straight up in the air to a height above the summits of Mauna Loa and Mauna Kea, and a flame of fire appeared at its top. It looked as if a little hill were being pushed straight up by a larger one until it burst into masses of sand and rock… Eruptions continued for some days and many were killed, the bodies of men, women, and children lying unmutilated just as they were when marching."

Hawai’I Volcanoes National Park Archaeologist Jadelyn Moniz Nakamura continues.

Nakamura: A huge explosive eruption occurred. It probably was a mixture of hot volcanic gas, steam, sand and ash that came down and engulfed the warriors. The third group coming up behind came upon them. They had all perished.

A third of Keoua’s army was killed. Kamakau writes, One of the seers told Keoua that Hiʻiaka, his beloved, was angry at him for leaving Hilo. In any case, the event was not seen as a good sign, and subsequently, Keoua was killed to sanctify Kamehameha’s new temple, Pu’ukohola in Kohala.

Fast forward to 1920, geologists discovered footprints in the Ka’u lava fields and tied them to Keoua’s ill fated army.

Nakamura: We now believe those footprints were not just from Keoua’s army but from other Hawaiians who were travelling through there on their everyday ventures.

These footprints, some over 200 years old, go in all directions. Over 200 other archaeological features have been found along this well used trail, including shelters and basalt quarries.

Nakamura: We found hundreds of these sites where they were sitting there making these adzes over a thousand acre area along the caldera’s edge. This was a major trail system and they knew this material was coming out of the volcano and it was an excellent material to use to make their tools. It was one of five quarry sites on the island.

So Hawaiians in 1790 were just going on with their business between eruptive events, passing through the ash, going into temporary shelters, quarrying basalt in the area.

Nakamura: It would have taken about a week for (the muddy ash) to dry and so they were walking through it and leaving their footprint impressions. There were two eruptive events that occurred, and there’s footprints that have been identified in both of those layers.

No matter what it’s a record of people walking barefoot over pahoehoe.

Nakamura: Hawaiians were incredible for being able to live in this very volcanic very active place. They understood their landscape and they understood what was happening.

Nakamura says the Ka’u desert’s forbidding black lava with occasional tall grasses and scrub looks antithetical to agriculture but what was useable was used well.

Nakamura: There’s an area in the Park called Kealakomo. It has agricultural remnants where they were growing sweet potato. If you go out there today and you look at this area, you wonder how in the world people were surviving here. One of the reasons why they decided to live and plant there was there was an ash deposit had been deposited there and in that ash deposit they were able to grow plants to eat. They were really looking across the landscape to where they could best thrive and survive.

Nakamura: After an explosive eruption, deposit the ash, and this is a good place to grow your crops.

Nakamura: Hawaii Volcanoes National park is home to thousands of archaeological features and really they are a testament to Hawaiian people’s ability to make their homes in these places on top of an active volcano.

Read Nakamura's account of the footprints here.

See a video of Nakamura explaining the footprints on site here.