When Isaiah Horace Cubberly was born on 1 September 1860, in Hamilton Township, Mercer, New Jersey, United States, his father, Pearson Alijah Cubberley, was 36 and his mother, Elizabeth Ann Asay, was 26. He married Mary Ellen Asay on 5 April 1886, in Trenton, Mercer, New Jersey, United States. They were the parents of at least 1 son and 2 daughters. He lived in New Jersey, United States in 1870 and Newark, Essex, New Jersey, United States in 1910. He died on 21 December 1941, in Orange, Essex, New Jersey, United States, at the age of 81.