Rachel Barclay was born in Falmouth and is known to have resided at Carenver, Stracey Road, Falmouth, in 1901. Earlier addresses include Helston, Carwinnion Cottage in Mawnan Smith, and Bideford (Devon). She had two sisters, Georgina and Isabella, the latter having been an art student.

Rachel first identified as an artist while staying in St Ives in 1911, and exhibited from then until 1916. She is known to have shown 98 paintings of gardens and landscapes at the Walker's Gallery, London. 

According to the Falmouth Packet & Cornwall Advertiser, and the Royal Cornwall Gazette in September 1888, Rachel Barclay's ornamental flower designs were shown at the Royal Cornwall Polytechnic Society. She was also an accomplished needlework embroiderer, and her name is recorded in the Cornish Telegraph of September 1908 as having exhibited at the Royal Cornwall Polytechnic Society in  Camborne.