He was Member of Parliament (MP) for South Fermanagh from 1885 to 1892, private secretary to the Irish leader Charles Stewart Parnell from 1880 to 1891, and Town Clerk of Dublin from 1893 to 1920.
Son of Patrick Campbell of Kilcoo, Co. Down, he began his career as a grocer's apprentice in Newry and was a member of the Catholic Young Men's Society.
The Corporation was controlled by Parnellites and Campbell won the post by a large majority over six other candidates on 24 May, in an election which was seen as a tribute to Parnell.
The Corporation then voted by 26–12 on 4 November 1920 to suspend him and his assistant Town Clerk, James Flood, who had declined to act in his place.
He is mentioned in the ‘Eumaeus’ chapter of James Joyce's Ulysses, where a jarvey is described as resembling the town clerk Henry Campbell.