Excerpts from Books and Wikipedia
"The Hawaiian army and navy developed from the warriors of Kona under Kamehameha I, who unified Hawaii in 1810. The army and navy used both traditional canoes and uniforms including helmets made of natural materials and loincloths (called the Malo) as well as western technology like artillery cannons, muskets, and European ships. European advisors were captured, treated well and became Hawaiian citizens. When Kamehameha died in 1819 he left his son Liholiho a large arsenal with tens of thousands of men and many warships. This helped put down the revolt at Kuamoʻo later in 1819 and Humehume's rebellion on Kauai in 1824.
During the Kamehameha Dynasty the population in Hawaii was ravaged by epidemics following the arrival of outsiders. The military shrank with the population, so by the end of the Dynasty there was no Hawaiian navy and an army consisting of several hundred troops. After a French invasion that sacked Honolulu in 1849 Kamehameha III sought treaties with the United States and Britain to become a protectorate state." [Wikipedia]