[3] In 1835 he volunteered for foreign service as colonel with the British Legion in Spain, which he himself had raised in the county of Cork and other parts of Munster, to sustain the cause of the Spanish Queen and constitution against the insurgent Carlists.

[3] Later on he became Deputy Adjutant-General, and ultimately succeeded Sir De Lacy Evans as general of brigade in command of the British Auxiliary Legion in Spain.

O'Connell was elected a member of the New South Wales Legislative Council in August 1845 for the electoral district of Port Phillip.

[6] He was appointed commissioner of crown lands for the Burnett district in 1848, became government resident at Port Curtis (now Gladstone) in 1854, and held this position until 1860.

[8] In 1865 O'Connell, Augustus Charles Gregory and John Douglas applied for a special grant of land to erect a Masonic Hall in Brisbane.