His older brother was Richard Cubitt Johnson who played cricket for Cambridge in 1850 and died while an undergraduate of typhoid fever in 1851.
Johnson attended school in Bury St Edmunds and was admitted to Clare College, Cambridge in 1853, graduating with a B.A.
He lived for a time in New Zealand, in Poverty Bay, and was a member of the Legislative Council from 1872 to 1892.
He was the father of Peter Randall Johnson, who was born while he was living in New Zealand.
[4] He had a younger brother, James Woodbine Johnson, who also emigrated to New Zealand (in 1866) and died there in 1899.