In 1810, Kamehameha I and King Kaumualii of Kauai formed an alliance whereby Kauai would remain a separate kingdom, but within the realm of Kamehameha I, so long as Kaumualii lived.
When Kaumualii died in Honolulu on May 26, 1824, Kaahumanu, ruling in Kamehameha II’s absence while he was away on a visit to England, then dispatched Kalanimoku to Kauai to effect a new regime ruled by Kamehameha II and herself.
When Kalanimoku arrived at Waimea on August 1, 1824, he informed Kauai chiefs that the island was indeed then under the dominion of Kamehameha II and Kaahumanu.
Consequently, on Sunday, Aug, 8, Kaumualii’s son, Humehume, led a faction of rebellious Kauai chiefs determined to maintain their independence by attacking the Russian Fort, which was garrisoned by defenders loyal to Kamehameha II and Kaahumanu.
After a 30-minute battle, the rebels were beaten off and fled to Hanapepe, leaving behind 10 dead, while 8 defenders were killed.
Kalanimoku then sent his pilot boat to Oahu for reinforcements.
Commanded by Governor Hoapili of Maui, as many as 1,000 warriors from Oahu and 300 to 400 volunteers from Maui arrived at Waimea and marched towards Hanapepe on Aug. 20.
Hoapili’s soldiers crossed the Hanapepe River and hiked to the approximate location of the Hanapepe Lookout, where Humehume and his men held a position behind a rock wall overlooking the valley.
Humehume’s rebels fired their small brass field piece three times at the attackers, who safely dropped to the ground beforehand each time.
Hoapili’s soldiers then opened up with muskets and the rebels broke ranks and ran for the woods, where they were pursued.
As many as 130 insurgents were slaughtered, while only 1 of Hoapili’s soldiers was killed.
Humehume escaped but was found in the mountains a few weeks later and was deported unharmed to Oahu.
Surviving rebel chiefs and their tenants were also deported to Oahu.
Even Kauai chiefs loyal to Kamehameha II and Kaahumanu were dispossessed of their lands and exiled.
Kauai was then divided principally among the relatives of Kamehameha I, who thenceforth ruled the commoners of Kauai.
Source: The Garden Island