Johnston, whose name was also spelt Johnstone, was born in
Ayrshire south-west Scotland in 1809, the son of Robert Johnstone, of the Ayrshire branch of
Clan Johnstone of Annandale, and his wife Mary (
née Woods). In 1838, he married Henrietta Charlotte Hatton, who was a devout
Roman Catholic. on 3 January 1843 on the
Prince of Wales. He travelled with his wife, their two sons
Walter Woods and Sydney and their daughter Agnes Mary who was born during the journey. In the early 1840s, he founded the large mercantile house and
stock and station agency known as Johnston and Co. and continued to take an active part until 1878, when he retired from business, leaving the company in the hands of his sons: the Hon.
Walter Johnston who, like his father, was an ex-Minister, and the Hon. Sir
Charles Johnston, M.L.C. Johnston also held land in Wellington and the lower
North Island Johnston was a member of the
Wellington Provincial Council between December 1855 and April 1872. He first represented the Wellington Country electorate, and since 1865 he was a member for
Karori and
Mākara. At various times (1858, 1861–1862, 1868), he was a member of the Wellington Executive Council. Johnston was appointed to the Legislative Council on 31 March 1857 and served until 6 November 1860, when his membership lapsed through absence. He was reappointed on 11 March 1861 and remained a member for the rest of his life. Johnston was prominent as a legislator for many years. His third daughter, Jessie Mary, married
Westby Perceval on 11 May 1880 at Wellington. Henrietta Johnston died on 23 February 1878. He died on 16 November 1887 at Wellington, aged 76 years, and was buried three days later. At his death, his property was estimated to be worth £1,000,000. ==Notes==