In 1905, Diggle was appointed Bishop of Carlisle, the diocesan bishop of the Diocese of Carlisle.[7] He was one of the most vociferous episcopal supporters of British involvement in the Great War. He blamed Prussian militarism and was appalled at what he regarded as German cruelty to Belgian and French civilians who had been overrun in the German advance. He regarded it as a spiritual war, the 'Good'of Britain and her allies facing the wickedness of Germany and, therefore, fighting for a choice between '...public law or military licence...freedom or absolutism, independence or servitude, truth or falsehood, purity or corruption, faith or force, love or hate, Christ or Beliel...'[8] He was very proud of clergy and their families who were especially active in the War. These included his own sons, Reginald, who won a MC as a chaplain, and Philip, who was a major in the Border Regiment;and Theodore Hardy, vicar of Hutton Roof, who was awarded the VC. His assistant, the Bishop of Barrow-in-Furness, who volunteered as a Chaplain and served with the Church Army, and the Vicar of Ambleside, who worked in a munitions factory during the week and returned to his parish at weekends to take services, were praised. Unlike most of his colleagues, he refused to forbid his clergy from joining the forces as combatants, writing 'If it is wrong for a clergyman to enlist, can he encourage others to enlist? If we honour and praise the dead for a sacred cause how can it be wrong for clergy to enlist in so noble a cause?'.[9] Diggle also refused to accept candidates for ordination if they were 'of military age and medically fit at this critical juncture in the nation's needs'.[10] One of Diggle's last tasks was to join President Wilson of the USA in the nonconformist chapel where Wilson's ancestors had worshipped, and was widely criticised since he was a CofE bishop. Diggle was unmoved and wanted to welcome the President on his visit to the diocese.[11] Diggle continued as bishop until his death on 24 March 1920.[12][13]
Personal life
In 1874, Diggle married Cicely Jane Butterfield. In 1884, Diggle married Edith Moss. Diggle had five children: four sons and one daughter.[14]