On this day in 1893, the Leper War on Kaua'i, also known as the Battle of Kalalau, began when members of the new colonial government arrived at Kalalau Valley to enforce a deportation order for an isolated leprosy colony there.

Following the overthrow of the Kingdom of Hawaii, the colonizers began enforcing the 1865 "Act to Prevent the Spread of Leprosy", which involved deporting or forcibly relocating anyone who had the disease to the Kalaupapa Leprosy Colony of Kalawao, on the island of Molokai.

On June 26th, a group led by deputy sheriff Louis Stoltz ventured deep into the Kalalau Valley to enforce this order. After they established an encampment, a band of lepers led by indigenous Hawaiian man Ko'olau (shown, with his family) seized the camp, and chased the lawmen back to the coast. The following day Ko'olau shot Stoltz dead while he was attempting to arrest a man named Paoa.

On July 1st, 1893, fifteen soldiers landed in Kalalau Valley, initally without incident. Over the next two weeks, Ko'olau, along with his wife Pi'ilani, led a campaign of guerilla warfare against state forces, compelling them to give up due to their inability to Ko'olau or evade his group's attacks.

Twenty seven lepers were captured and sent to Kalawao, while the remaining lepers were never harassed again. The leper community dissolved, living in individual households.

Ko'olau and his family remained unharmed, but hid in the valley for the remainder of his life. After Ko'olau's death, his wife Pi'ilani left the valley to share their story, which was published in 1906 as Ka Moolelo oiaio o Kaluaikoolau ("The True Story of Kaluaikoolau").