Dunn's close friendship with Max Aitken continued after the wealthy New Brunswicker also chose to live in England. Still very much in touch with his roots, after a 1911 fire destroyed the bells of Christ Church Cathedral in Fredericton, James Dunn donated the replacements for the original 1849 five-ton bells. The First World War provided him with a number of business opportunities and to the ability to serve Britain. For his World War I efforts, he was created a baronet in the 1921 New Year Honours.