Daniel McCorriston (1840-1927) and Hugh McCorriston (1836-1926) and their families were lucky to have many relatives throughout the Hawaiian Islands in the late 19th and early 20th centuries. In addition to the families to whom they were related through marriage—the Meyers, the Cummins, and the Atcherleys, significantly—they also had a number of cousins living in Hawaii.
One such cousin was John C. McColgan (1814-1890), who immigrated from County Londonderry, Ireland, via Manchester and San Francisco in 1849. Likely the son of an older sister of Hugh McCorriston (1805-1848) and Daniel McCorriston (c. 1820-c. 1850), McColgan was a prominent fixture in Hawaiian society until his death in 1890. 
A Little About John C. McColgan
John C. McColgan, also known as John Kamanoulu, was a tailor, sugarcane planter, and businessman in the Kingdom of Hawaii in the latter half of the 19th century. He owned plantations on Oʻahu and Molokai—the McColgan Plantation and the Kamalo Sugar Plantation, respectively—and was known for bringing the first sewing machine to the Hawaiian Islands.    
John McColgan was the biological father of Kini Kapahu Wilson (1872-1962), a world-renowned hula dancer and second wife of the Mayor of Honolulu, John Henry Wilson (1871-1956). He was also the biological father of Mary Piʻia McColgan (1862-1951); of John Hiram McColgan (1854–1936), an employee of the Honolulu Iron Works; and of John Kekaua Kamanoulu (1867–1927), a representative to the Territorial Government and husband of Deborah Kamālie Pahau, who was the biological half-sister of Queen Liliʻuokalani’s hanai son John ʻAimoku Dominis. He had five other biological children with his Hawaiian wife Kalaʻiolele who survived into adulthood and who are unknown at the time of writing.    
The McCorristons, John McColgan, and Sugar
From at least 1872, John McColgan owned and operated a plantation in Halawa, Oʻahu. By 1877, he had moved or expanded his operations to Kamalō on Molokai, growing sugarcane on 300 acres of virgin soil.  
By 1880, Daniel McCorriston was managing McColgan’s plantation—the Kamalo Sugar Plantation—and Hugh McCorriston was a sugar refiner for the same. The McCorriston Brothers shared management duties by 1888, and took over ownership of the Kamalo Sugar Plantation in 1890, as they were the recipients of “all the rest and residue of [McColgan’s] estate, real, personal or mixed, and all Trust funds or property that may be remaining …”.     
The Legacy of the McCorristons and John McColgan
The legacy of the McCorriston Brothers and John McColgan is seen in both the demographics of Hawaii itself and, indirectly, in the current-day sugar industry.
When sugar plantations began production on a large scale in the mid-1800s, owners began hiring foreign laborers, as Native Hawaiians were more content to subsist off the land instead of going into plantation farming. This hiring practice drastically changed the demographics of Hawaii, as thousands of Chinese, Japanese, Portuguese, Filipino, and Korean laborers came to Hawaii and stayed.  
In the 1870s, Daniel McCorriston hired 15 Chinese farm laborers from California to work on his and Hugh’s plantation in Kamalō. At the time of hiring, there were only two Chinese people on the Island of Molokai; Daniel’s hiring practice increased the Chinese population of Molokai nearly eightfold and contributed to the shift in Hawaii’s demographics from roughly 75% Native Hawaiian in 1878 to the current-day “mixed-plate,” in which everyone is an ethnic minority.  
From this same hire comes the McCorristons’ and McColgan’s indirect tie to the present-day sugar industry: one of the McCorristons’ plantation workers, Chun Ah Ping—who became the father-in-law of Aileen McCorriston (1900-1982), Daniel’s youngest daughter—moved to “Puunene plantation” in about 1879; Puʻunene plantation belonged to Claus Spreckels of the Hawaiian Commercial and Sugar Company (HC&S). HC&S became part of the California & Hawaii Sugar cooperative in 1906, a company that exists today as a subsidiary of ASR Group and provides the lion’s share of refined sugar in the American West.   
The legacy of the McCorristons in relation to John McColgan also lived through McColgan’s biological daughter Kini Kapahu Wilson and her husband, John Henry Wilson.
In 1942, Daniel’s son Edward McCorriston (1872-1945) and John Wilson embarked on a project to help alleviate food shortages due to World War II. Wilson conceived of a plan to restore ancient Hawaiian fishponds to feed the people and enlisted Edward’s help. Edward took control of Molokai, enumerating 54 fishponds “in good to useless condition”; John took control of Oʻahu. While the project was ultimately not put into action, owing to the outsized cost of dredging fifty fishponds, the men’s report contributed to the current store of knowledge about ancient Hawaiian fish ponds. 
The McCorriston cousins—Daniel and Hugh McCorriston, and John McColgan—made a lasting impact on Hawaii, her demographics, her culture, and her industry.
Updated February 1, 2019.
An old resident gone (1890, March 1), The Honolulu Advertiser. Retrieved from https://www.newspapers.com/clip/19316702/obituary_of_john_mccolgan_18141890/
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