Christian Missionaries enforced law to prevent whalers and sailors from creating moral degradation in the town by drinking and debauchery.

Following these incidents, the fort was then built at the initiative of Queen Kaʻahumanu (1768–1832) the then regent of Kuhina Nui to quell disturbances to the people of Lahaina from the ship whalers.

[1] In the period between 1830 and 1860, American whaling fleets frequented the Lahaina port town which resulted in growth of the economy of the island and brought about modernization.

[1] With increasing conversions to Christianity the missionaries prevailed on Hoapili, the Governor of Maui, to promulgate laws to prohibit sale of liquor and banning native woman from soliciting by visiting the ships (women used to swim across to ships to meet the sailors[2])[1] Initial measures taken by the Christian missionaries of the town by enforcing laws (a kapu, the ancient Hawaiian code of conduct of laws and regulations of Hawaii proclaimed in 1825) to prevent the native women visiting the ships or and to prevent the whaling community and sailors from visiting the town after nightfall, in pursuit of pleasure, embittered the sailors and whalers.

[3] The “sea-bittered sailors”[1] were not pleased with these stringent regulations, and in 1825 the English whaler Daniel caused rioting in the town for three days and even gave out life threats to Reverend William Richards.

A visitor noted: “must be off to their ships, or into the fort”, who also noted the condition of the sailors in the prison as: “caressed and hung upon by native girls, who flock here in the ship season, from other parts, to get the ready wages of sin.”[1] In 1841, American naval officer Charles Wilkes (1798–1877) who visited Lahaina Fort as commanding officer of the United States Exploring Expedition observed: "After the king's palace, the fort is the most conspicuous object: it is of little account, however, as a defence, serving chiefly to confine unruly subjects and sailors in.

Defense reinforcements were provided on the top of the fort in the form of cannons; the canons were 47 numbers of different sizes, which had been recovered from the shipwrecks in various regions of Hawaii.

In 1848, Henery Wise who visited Lahaina Fort, where the then governor was residing, noted: “[It is] a large square enclosure constructed of red coral rocks, banked up fifteen feet with earth , and mounting an oddly resorted battery of some thirty pieces of artillery, of all sorts of cartridges , and claibre long, short, and medium; they commanded the usual anchorage and no doubt very well to prevent any acts of violence from merchant ships; but it is a question, if, at the second discharging of shot, they do not tremble to pieces.

Another notable daily event at the fort was the beating of the drums at dusk by guards as a signal (a curfew) to the sailors on land to go back to their ships.

No person is allowed to remain on shore over night, unless furnished with a proper pass by the captain of the port; and any one found on the beach, or in the town, with no pass, after the proper time, is marched to the calboose, where he is kept in confinement till morning, and then muleted in a pretty round sum for breaking the laws.