Background
He was born in Morayshire, the son of William Johnston and Isabel Hepburn.
He was born in Morayshire, the son of William Johnston and Isabel Hepburn.
He represented Saint John County in the Legislative Assembly of New Brunswick from 1802 to 1820. He set up business at Saint John, New Brunswick in the 1780s. Johnston traded fish and lumber for sugar and molasses from the West Indies which was used to manufacture rum in Scotland.
Johnston was a director of the Bank of New Brunswick and a port warden for the harbour at Saint John.
Johnston was named a magistrate for Saint John County in 1818. He died in Saint John at the age of 73.