A native of Dumfriesshire, Scotland, John Cunningham was born in 1792 and became a foreman of Saint John in 1818, being described as a labourer. He advertised as a stone cutter and mason in 1821, and was commissioned by Henry Gilbert in 1822 for his neoclassical house near Haymarket Square. This is the first known design and building that was complete by Cunningham. He acted as both a builder and an architect until the mid 1830s when he then concentrated on solo projects.

Cunningham's work includes the spires atop Stone Church (1826), the Bank of New Brunswick (1826), the Saint John County Gaol (1836), the City Market (1837), Centenary Church (1838), Wesleyan Methodist Church (1840), and the Customs House (1841). Most of these buildings have since been destroyed.

Cunningham designed and supervised the construction of other buildings around the province, including the St. Andrews Goal (1837), and Christ Church Cathedral (1845). The severe depression in the early 1840s caused him to declare bankruptcy in 1843, and between 1855 and 1867 he worked in Chelsea, Massachusetts.

Cunningham designed in various styles - Neoclassical, Gothic and Classic Revivals, Italianate, and Second Empire. This indicated John Cunningham's enthusiasm for the adoption of new styles. He was Saint John's dominant architect for a quarter century, and his work linked Saint John to architectural developments in Britain. He died in Chelsea, Massachusetts, near Boston, on 25 November 1872.

Source: Copied almost verbatim from: http://www.saintjohn.nbcc.nb.ca/heritage/architecture/Cunningham.htm. Also a few references from Daniel F. Johnson's Vital Statistics from New Brunswick Newspapers on-line.