John was educated at Cork Grammer School and Edinburgh University, and qualified L.R.C.P., and L.R.F.P.S. in 1910. He then went as a Ship's Surgeon to West Africa, and afterwards to Canada. On the outbreak of war he volunteered and on 6th December 1914 gained a commission at the rank of Lieutenant in the R.A.M.C. He went to France on 20th May 1915, and was killed at Hooge by a shell. His Colonel wrote to his family: "Your gallant son was beloved by officers and men for his genial pleasant manner and his genuine Irish wit, and his devotion to the wounded. He was a splendid professional man, and the battalion has suffered a severe loss by his death." Colonel Porter, Director of Medical Services also wrote: "He was killed instantaneously by a shell, when advancing with his regiment near Hooge. They were about to take part in an assault on some trenches previously lost by another brigade. He bore the reputation of being a very gallant man, and one devoted to the cate and succour of the wounded. He has now joined our band of heroes of the R.A.M.C., and his name will live on our annals and he himself in our memories as one who has conferred honour on the corps." John was the second son of William and Martha Elizabeth Hawkes of Castletown, Bere, Co. Cork.