John Leonard was born on 6 November 1812 to William and Ann Leonard of Hadlow, Kent, England
John Leonard married Jane Cheesman on 12 February 1839, at the Parish Church of Hawkhurst, Kent, England.
The England and Wales Census records his occupation as follows:
- 1851 – Blacksmith employing 2 men
- 1861 – Farmer 9 acres employing 1 man
- 1871 – Farmer
- 1881 – Farmer 5 acres hops
- 1891 – Retired Farmer