Henry Nettleship was born at Kettering in Northamptonshire on May 5, 1839. His father, Henry John Nettleship, a solicitor practising in that town, married Isabella Ann, daughter of the Rev. James Hogg, Vicar of Geddington, and master of Kettering Grammar School. They had seven children, of whom five boys lived to maturity. The youngest of these, Richard Lewis, Fellow and Tutor of Balliol College, Oxford, perished in a snowstorm on Mont Blanc, August 25, 1892. Of the other brothers, one became an artist, another an oculist, a third a schoolmaster; while the eldest is the subject of this memoir.

His grandfather, John Nettleship, of Tickhill, Yorkshire, married Ann Hunt (first cousin of George Waddington, Dean of Durham), whose brother, J. H. Hunt, was the editor of the Critical Review and the translator of Tasso. John Nettleship's mother, the Mrs. Nettleship of Gainsborough spoken of with admiration by Mr. Mozley in his Reminiscences of Towns, Villages and Schools, was a remarkable woman, cultivated and musical, pious and charitable. The mother of the late Prof. George Rolleston was one of her daughters.

His grandmother's connexion with Dean Waddington was the cause of his being eventually sent to school at Durham, and this, by bringing him under the influence of Dr. Elder, the Headmaster, determined his future career as a Scholar.

His feeling for music and poetry seems to have been derived from his father's family, who were all musical, an aunt being an accomplished pianist.