When James Blakeslee was born on 18 July 1802, in Milton, Chittenden, Vermont, United States, his father, David Blakeslee, was 36 and his mother, Julia Redfield, was 33. He married Louisanna Edmunds on 9 October 1825, in New York, United States. They were the parents of at least 3 sons and 3 daughters. He lived in Kane, Illinois, United States in 1860. He died on 18 December 1866, in Batavia, Kane, Illinois, United States, at the age of 64, and was buried in Batavia, Kane, Illinois, United States.