[1][2] Interested in early English literature, Southern in 1820 founded the Retrospective Review, which he edited on his own till 1826, by which time 14 volumes had been published.
[1] When Jeremy Bentham founded the Westminster Review in 1824, Southern was for a time co-editor with John Bowring; and in 1825 he became proprietor and editor of the second series of the later London Magazine.
[1] In 1833 Southern accompanied the English ambassador, George William Frederick Villiers to Spain as his private secretary.
He was then placed on the diplomatic staff, and, after remaining some years at Madrid, was appointed secretary to the legation at Lisbon.
[1] In 1848 Southern became minister to the Argentine Confederation, and in 1851 was promoted to the court of Brazil, and received the insignia of a Companion of the Bath.