Kamehameha was especially fortunate in securing the services of John Young and Isaac Davis, who took an active part in the campaigns of the final conquest. (Kalākaua)
They arrived in Hawai‘i at the same time (on different boats) and they served Kamehameha I as co-advisors. John Young, a boatswain on the British fur trading vessel, Eleanora, was stranded on the Island of Hawai‘i in 1790.
Isaac Davis (Welch) arrived in Hawaii in 1790 as the sole survivor of the massacre of the crew of The Fair American. He became one of the closest advisors to Kamehameha I.
When Captain George Vancouver visited Hawai‘i Island in 1793, he observed that both Young and Davis “are in his (Kamehameha’s) most perfect confidence, attend him in all his excursions of business or pleasure, or expeditions of war or enterprise; and are in the habit of daily experiencing from him the greatest respect, and the highest degree of esteem and regard.”
Because of their knowledge of European warfare, Young and Davis are said to have trained Kamehameha and his men in the use of muskets and cannons. In addition, both Young and Davis fought alongside Kamehameha in his many battles.
In 1824, Liholiho (King Kamehameha II), his wife, Kamāmalu, and a group of retainers and foreign advisors, traveled from Hawai‘i to England. Liholiho and his wife died there, and in May of 1825, their bodies were returned to Hawai‘i by Lord Byron.
One of the crew members, James Macrae, a botanist, wrote narratives of the journey and what he learned while there – the following are two accounts of battles, told by Macrae – first, the taking of Hawaiʻi and then the conquest of Oʻahu:
“Mr. Goodrich (a missionary there) informed us that it was at this ravine that Mr. Young and Mr. Davis had fought their first battle in the service of Tamahamaah (Kamehameha) and defeated upwards of 10,000 of the enemy with only 300 on their own side, before their leader came up to their assistance with the main body of the army.”
“The description related to us of this engagement was that when King Tamahamaah had conquered the south side of Owhyee (hawaiʻi,) he soon after, with his army, marched round to the opposite side of the island by the east, taking with him Young and Davis for the first time, to whom he gave command of the chief part of his army.”
“The chief of the Heddo part of the island was prepared to meet Tamahamaah in order to defend his proportion of the island from being subjected to the other’s power, but on seeing the superior force of Tamahamaah, this chief kept retreating to the west till overtaken by Young and Davis, who were nearly a day’s journey in advance of the main body of the army.”
“The attack took place early in the afternoon from the opposite sides of the ravine in the wood, when after several hours engagement, it was decided in favor of Young and Davis, who alone had firearms.”
“These two killed the enemy in vast numbers from the crowded manner in which they stood to oppose them, being unacquainted with the destructive effects of firearms.”
“This battle gave Tamahamaah the conquest of Owhyee.”
Next, was the conquest of Oʻahu and the Battle of Nuʻuanu:
“When Tamahamaah with Young and Davis and the rest of his army had landed from their small fleet in the harbour, without opposition from Tereaboo (Kalanikupule,) they found that the latter had collected his forces above the town in Hanarura valley.”
“Tamahamaah could not have wished for a better situation or one more favourable to his purpose, the valley being overhung by ridges on each side, which were left unoccupied by the enemy.”
“Tamahamaah, without any opposition from the enemy, placed a number of his men on the side ridges, and then he himself, accompanied by Young, Davis and the greater part of his army, took up their position in the center of the valley.”
“They had with them only one small swivel and a few firearms, the rest being armed with spears and clubs. Yr. Davis, who had the swivel, somewhat singular to relate, killed Tereaboo’s general on his firing the first shot, before the engagement had scarcely begun.”
“When this happened, as is usual with these natives, they instantly got into confusion and retreated. Tamahamaah pursued them up the valley, and on coming to the precipice they threw themselves over and were found in the thousands, lifeless at the bottom of the cliff.”
“Thus did Tamahamaah, with the help of Young and Davis, and with hardly any firearms, easily conquer this important island, which may now be considered the first of the Sandwich Islands on account of its good harbour.”
“The king of Woahoo fled to the mountains, being convinced that the custom of putting the vanquished to death would be practiced upon him. ‘I must die,’ he said to one of his friend’s, ‘for I will not let Tamahamaah enjoy this triumph. I will sacrifice myself to the gods.’ His corpse was afterwards found in a cave in the mountains.”
The image shows an Herb Kane depiction of the Battle of Nuʻuanu.