When Isaac Tietsoort was born in 1690, in Kingston, Ulster, New York Colony, British Colonial America, his father, Willem Abrahamse Tietsoort, was 42 and his mother, Neeltje Teunise Swart, was 40. He married Sara Liewens on 9 June 1720, in Kingston, Ulster, New York, United States. They were the parents of at least 5 sons and 3 daughters. He died on 16 November 1757, in Newton, Sussex, New Jersey, British Colonial America, at the age of 67.