He joined the Royal Artillery late in World War I, serving in Palestine from 1918 to 1919,[2] retiring as Lieutenant.
[1] After his army service Campbell turned his attention to business and politics in Northern Ireland.
In a by-election of 11 February 1943 he was elected as Member of the United Kingdom Parliament for Antrim, succeeding his father-in-law Sir Joseph McConnell who had died the previous year.
On 26 August 1943 in a byelection following the resignation of John Fawcett Gordon, he was elected to the Northern Ireland Parliament as member for Carrick.
[2] He held these posts until death aged 46 in 1945 when his plane crashed in the Adriatic Sea during a parliamentary fact finding visit to Italy.