Hunter was born on 30 May 1846 in Aberdeen, Scotland (GRO), and moved to London, where he exhibited both at Smith Street and the RA.  1897 found him in Cornwall, where he lived at Belle Vue, Newlyn, and from 1902 moved to The Malt House where he stayed until his death. Hunter assisted in teaching at the FORBES School of painting in the early days of the School.

Constance BIRCH wrote in her biography of Stanhope FORBES and Elizabeth FORBES: 'Among the older painters of the colony...Mr and Mrs Forbes feel that they owe a debt of gratitude to Mr G S Hunter, an artist of sincere and thoughtful individuality who is always ready to help and supplement the teacher's efforts. His own studio...is a perfect treasure-house of beautiful and interesting work.'

At the 1895 Opening of NAG, Hunter exhibited three paintings - two from the 'memorable East' (Cornishman review cutting): A Jericho Patriarch and A Modern Canaanite Jerusalem (which both sold), and the third being a Spanish subject. In 1901 at NAG he showed West Coast of Scotland and in 1907 he sold Spanish Girl. The artist died on 18 June, 1919, age 73, in Newlyn.