He was born in Kragerø, Norway as the son of merchant and politician Johan Christian Heuch (1794–1843) and his wife Christine Elisabeth Bonnevie (1803–1863).

[1] His paternal grandfather Peter Andreas Heuch (1756–1825) was among the wealthiest persons in Southern Norway.

[1] Their daughter Kristine Elisabeth married barrister Fredrik Moltke Bugge.

His father died before J. C. turned five years old, and at the age of fifteen he moved to Christiania to be educated.

[1] Due to his health he had to take a sabbatical in Rome from 1873 to 1874, but when he returned to Norway he was hired as a priest working in municipal and private institutions of Christiania.

[1] He referred to Jens Jonas Jansen, a priest on the liberal side of the spectrum, as a "dangerous" man in 1902.

[5] Other adversaries of his in the public debate were Arne Garborg, Bjørnstjerne Bjørnson (whom he nonetheless knew on a personal level), Georg Brandes, and liberal ideologist Ernst Sars.