Background
Johnston was the eldest son of John Brett Johnston of Ballykilbeg, company Down, and his wife Thomasina Anne Brunette Scott, daughter of Thomas Scott.
Johnston was the eldest son of John Brett Johnston of Ballykilbeg, company Down, and his wife Thomasina Anne Brunette Scott, daughter of Thomas Scott.
He was educated at Trinity College, Dublin being awarded Bachelor of Arts in 1852 and Master of Arts
He is noted for his opposition to the Party Emblems Acting and Party Processions Acting, which banned Orange marches. In 1856. In 1857 he stood unsuccessfully for parliament at Downpatrick. In 1867, Johnston organised an Orange Order parade from Bangor to Newtownards in County Down despite the Party Procession Acts.
The parade took part on 12 July 1867 and about 30,000 took part.
Johnston was sentenced to a short term in prison the next year for his actions. He was called to the Bar at King"s Inns Dublin in 1872.
Johnston was Inspector of Fisheries in Ireland from 1878 to 1885. In 1885 he was elected an independent Member of Parliament for Belfast South until his death.
Johnston married firstly in 1853, Harriet Allen daughter of Robert Allen of Kilkenny.
He was the father of Charles Johnston (1867–1931).
Orange Order; 20th United Kingdom Parliament. 21st United Kingdom Parliament. 23rd United Kingdom Parliament.
24th United Kingdom Parliament.
25th United Kingdom Parliament. 26th United Kingdom Parliament.
27th United Kingdom Parliament]
He was also elected as Member of Parliament for Belfast in 1868 and held the seat until 1878.