He was born in Southampton on 19 April 1850. He was grandson of John Gregory, engineer-in-chief of the auxiliary engines in Sir John Franklin"s last Arctic expedition, and was eldest child (in a family of three sons and five daughters) of Edward Gregory, a ship"s engineer, and Mary Ann Taylor.
On leaving Doctor Cruikshank"s private school at fifteen he entered the drawing-office, in his native town, of the Peninsular and Oriental Steam Navigation Company, in whose employ his father sailed. He had set his mind upon being a painter. In 1869, Gregory went to London, and with Herkomer joined the South Kensington Art School.
Subsequently he studied for a short time at the Royal Academy.
Gregory at first contributed sketches from the theatres, but soon freely transcribed sketches sent home from the French army at the front by Mr. Sydney P. Hall. In 1909, until his death, Gregory was president of the Royal Birmingham Society of Artists.
He died at his residence, Brompton House, Great Marlow, on 22 June 1909, and was buried in Great Marlow churchyard.
John's mark as a painter was made by an oil painting, "Dawn", originally shown at Deschamps' gallery in 1879; and "Boulter's Lock". Much of his best work appeared at the exhibitions of the Royal Institute of Painters in Water Colours. He contributed to the Academy several portraits, including that of Duncan McLaren MP, a replica of which is in the Scottish National Portrait Gallery.
