[4] At the end of his service in the Royal Navy, he became the founding CEO of the British Irish Chamber of Commerce, a post he held for three years during which time he lived in Dublin with his family.

[5][6] Aiken was one of three Ulster Unionist Party (UUP) candidates to run in South Antrim at the 2016 Northern Ireland Assembly election.

[12][13] He was elected unopposed as leader in November 2019 and led the party through difficult periods addressing concerns about Brexit, the Protocol and pandemic.

[14] He promptly opted for the UUP to take the Ministry of Health Department, when no other party would take it, and appointed Mr Swann MLA as Minister.

[17] In October 2021 Aiken was reselected to be a UUP candidate for South Antrim in the 2022 Northern Ireland Assembly election.