Many of the problems that Aden had suffered in its time as a colony did not improve as a federated state. In the new federation the Aden Trade Union Congress (ATUC) had a large influence in the new assembly and to prevent it seizing control of the federation in 1962 the former Colony of Aden had joined the Federation of South Arabia so that Aden's pro-British assembly members could counter the ATUC's influence.
However, the day after State of Aden joined the federation the Muhammad al-Badr of the Yemenese monarchy was overthrown and civil war ensued between forces backed by Gamal Abdel Nasser such as the National Liberation Front (NLF) and monarchist forces backed by the Saudi Arabia and the United Kingdom. Internal disturbances continued and intensified, leading on 10 December 1963 to the Aden Emergency, when a state of emergency was declared in the largely dysfunctional Aden State.
On 30 November 1967 Aden State, together with the federation, became the People's Republic of South Yemen. In line with other formerly British Arab territories in the Middle East, the independent state did not join the British Commonwealth. The South Arabian dinar, however, continued at the one to one parity with sterling until 1972.
