Charles Knox (died 1825), Archdeacon of Armagh, and his wife, Hannah, the daughter of Robert Bent MP.

Educated at Trinity College, Dublin, he took the degree of Bachelor of Arts at the age of twenty-one,[2] then graduated with an MA in 1834.

Knox was nominated to the see of Down, Connor, and Dromore by George Villiers, 4th Earl of Clarendon, at the time Lord Lieutenant of Ireland.

Samuel Wilberforce later reported in his diary for 26 August 1861, some gossip about this appointment; James Henthorn Todd had said of Knox that he was "…very foolish, without learning, piety, judgment, conduct, sense, appointed by a job, that his uncle should resign Limerick", while Anthony La Touche Kirwan (Dean of Limerick, died 1868), said that Knox "…used, when made to preach by his uncle, to get me to write his sermon, and could not deliver it".

As Bishop of Down, Connor, and Dromore, he hoped to build a new cathedral in Belfast, but abandoned this plan in favour of another, to increase the number of churches of the united diocese.