Born in 1886, Harold Kainalu Long Castle was descended from successful Hawai‘i businessman, James Bicknell Castle, who was a partner of Castle & Cooke. Harold K.L. Castle purchased the title to 9,500 acres in the Kailua ahupua‘a in early 1917.
Realizing that the Windward side of the island of O‘ahu was a beautiful place to live and could become a vibrant community, Harold K.L. Castle and his wife Alice Hedemann Castle set out to do their part in building that community. Mr. Castle donated land for churches of all different denominations because he felt that churches would bring congregations, congregations would bring stability, and that would benefit the community that was growing around them. Mr. Castle also donated land and money to Hawai‘i Loa College, Castle Hospital, ‘Iolani School, Castle High School and Kainalu Elementary School and the Mokapu peninsula land, which would become the Kāne‘ohe Marine Corps Base.
The Harold K.L. Castle Foundation was founded in 1962 by Harold K.L. Castle. Upon his death in 1967, Mr. Castle bequeathed a sizeable portion of his real estate assets to the Foundation. These assets, which have all been converted from real estate holdings to a diverse portfolio of securities, are the base from which the Foundation’s grants are made. Harold Castle’s son, James C. Castle, was a Director of the Foundation since its inception, and succeeded Harold Castle as President in 1968. He held this position until his death in 1994. In 1994, James C. McIntosh was elected President and served as Chair until 2013. James C. McIntosh is a grandson of Harold and Alice Castle, as was the late Director, John C. Baldwin.
The Foundation is the largest private foundation based in Hawai‘i. Each year the Directors award grants to nonprofit organizations benefiting the people of the State of Hawai‘i. Originally, grants focused on the Windward side of O‘ahu, youth, private education, arts and culture, and health care. The Foundation’s current investments are focused on public education redesign and enhancement, nearshore marine resource conservation, and strengthening the communities of Windward O‘ahu. Since its inception, the Harold K.L. Castle Foundation has awarded over $176 million in grants, with more than $60 million going to organizations serving Windward O‘ahu. Currently, the Foundation disburses an average of $6 million in grants per year.