Aden was a

battle honour A battle honour is an award of a right by a government or sovereign to a military unit to emblazon the name of a battle or Military operation, operation on its flags ("colours"), uniforms or other accessories where ornamentation is possible. In ...

awarded to units of the

British British may refer to: Peoples, culture, and language * British people, nationals or natives of the United Kingdom, British Overseas Territories and Crown Dependencies. * British national identity, the characteristics of British people and culture ...

and Imperial Armies that took part in either of the following campaigns:T.F. Mill
South Arabia 1915-1918
(archive of Regiments.org page) * The

Aden Expedition The Aden Expedition was a naval operation that the British Royal Navy carried out in January 1839. Following Britain's decision to invade the Port of Aden as a coaling station for the steamers sailing the new Suez-Bombay route, the Sultan of ...

, January 1839 * The Campaign in South Arabia during the Great War, July 1915 to October 1918 This award is unusual in that it was awarded for two entirely unconnected campaigns, undifferenced by year.

References

Battle honours of the British Army Colony of Aden Yemeni awards United Kingdom–Yemen relations Awards established in 1839 {{Orders-medals-stub