In 1778, Captain
James Cook arrived at Waimea Bay, the first European known to have reached the Hawaiʻian islands. He named the archipelago after his patron the 6th Earl of Sandwich, George Montagu.
During the reign of
King Kamehameha, the islands of Kauaʻi and Niʻihau were the last Hawaiʻian Islands to join his
ʻi. Their ruler,
ʻi, resisted Kamehameha for years. King Kamehameha twice prepared a huge armada of ships and canoes to take the islands by force, and twice failed; once due to a storm, and once due to an
epidemic. In the face of the threat of a further invasion, however, Kaumualiʻi decided to join the kingdom without bloodshed, and became Kamehameha's vassal in 1810. He ceded the island to the Kingdom of Hawaiʻi upon his death in 1824.
In 1815, a ship from the
Russian-American Company was wrecked on the island. In 1816, an agreement was signed by
Kaumualiʻi to allow the Russians to build
Fort Elizabeth. It was an attempt by Kaumuali’i to gain support from the Russians against
Kamehameha I. Construction was begun in 1817, but in July of that year under mounting resistance of
Native Hawaiians and American traders the Russians were expelled.
Old Sugar Mill of Koloa
In 1835, Old Koloa Town opened a sugar mill.
 From 1906 to 1934 the office of
County Clerk was held by
John Mahiʻai Kāneakua, who had been active in attempts to restore Queen
Liliuokalani to the throne after the United States takeover of Hawaiʻi in 1893.
Etymology and language
Hawaiian narrative locates the name's origin in the legend of
Polynesian navigator credited with discovery of the Hawaiʻian Islands. The story relates how he named the island of Kauaʻi after a favorite son; a possible translation of Kauaʻi is "place around the neck", describing how a father would carry a favorite child. Another possible translation is "food season".
Kauaʻi was known for its distinct dialect of the
Hawaiian language; this survives on
ʻihau. While the standard language today adopts the dialect of
ʻi island, which has the sound [k], the Kauaʻi dialect was known for pronouncing this as [t]. In effect, Kauaʻi dialect retained the old pan-Polynesian /t/, while "standard" Hawaiʻi dialect has changed it to the [k]. Therefore, the native name for Kauaʻi was said as Tauaʻi, and the major settlement of
ʻa would have been pronounced as Tapaʻa.