When Benjamin Adam Johnston was born on 25 September 1845, in Cornwall, Stormont, Ontario, Canada, his father, Robert Osborne Johnston, was 23 and his mother, Amanda Phoebe Eastman, was 23. He married Harriet Ann Snetsinger on 27 November 1867, in Stormont, Ontario, Canada. They were the parents of at least 2 sons and 2 daughters. He lived in Cornwall, Cornwall, Stormont, Canada West, British Colonial America in 1871 and Stormont, Ontario, Canada in 1901. He died on 28 November 1909, in Cornwall, Stormont, Ontario, Canada, at the age of 64, and was buried in Ontario, Canada.