Hitchcock was born November 9, 1891 on Molokaʻi island in the Kingdom of Hawaii. His father was Harvey Rexford Hitchcock, Sr. (1864–?). His paternal grandparents were Edward Griffin Hitchcock (1837–1898), son of Reverend Harvey Rexford Hitchcock (1800–1855), and Mary Tenney Castle (1838–1926), daughter of Castle & Cooke founder Samuel Northrup Castle (1808–1894). His mother was Hannah Julia Meyer (1866–1912) who was daughter of Rudolph Wilhelm Meyer. His father's first cousin was painter David Howard Hitchcock (1861–1943). He also had a great-uncle named Harvey Rexford Hitchcock, Jr. who lived 1835–1891 and published a dictionary of the Hawaiian language while principal of Lahainaluna School.