SUMMARY
Note to reader: this Country page primarily contains brief information about state-based violence during the period 1946-1974, and to some extent 1975-1988. For more detailed information on organized violence after 1989, please consult the specific Conflict and Dyad pages available on the left-hand side of this page. These pages contain more detailed information regarding all three categories of organized violence in this country from 1989 and onwards (when applicable), as well as detailed information about state-based violence 1975-1988. The left-hand side menu also contains links to Actor pages for all groups involved in organized violence since 1989 in this country, as well as actors involved in state-based violence 1975-1988.
History of South Yemen and unification with the North
In the 19th century the southern part of Yemen became a British colony, whereas the northern part of the country came under the rule of the Ottoman Empire. Upon the end of the First World War North Yemen gained independence upon the collapse of the Ottoman Empire. In colonial South Yemen, pro-independence movements emerged in the 1960s. The British colonial holdings in southern Yemen, some of which had existed as semi-autonomous protectorates, were consolidated into the Federation of South Arabia, itself a British protectorate, as a first step towards self-rule in 1964. The NLF (National Liberation Front) and the FLOSY (Front for the Liberation of Southern Yemen) fought the British colonial power from 1964 to 1967. As a result of the conflict, the British rulers transferred authority to the most powerful of the groups, the NLF, and granted independence to the People’s Republic of Yemen (commonly known as South Yemen, or occasionally as South Arabia) in 1967. The NLF was reformed into the Yemeni Socialist Party (YSP) in 1978.
The relations between independent socialist South Yemen and western-oriented North Yemen were strained at times and a short interstate conflict occurred in 1979. South Yemen also financially supported an opposition coalition in North Yemen, the leftist NDF (National Democratic Front), which fought the government in an intrastate conflict from 1979 to 1982. The relations between independent socialist South Yemen and western-oriented North Yemen were strained at times and common border conflicts occurred in 1972 and 1978-1979. In 1979, South Yemen received secondary warring support from Ethiopia in the interstate conflict with North Yemen. South Yemen also financially supported an opposition coalition in North Yemen, the leftist National Democratic Front (NDF), which fought the government in an intrastate conflict from 1980-1982. From 1972 to 1975, South Yemen also provided secondary warring support to the PFLOAG (Popular Front for the Liberation of the Arabian Gulf) against the government of Oman.
In South Yemen, a faction of the ruling Yemenite Socialist Party, later called the Zumra, engaged in a short intrastate conflict against the Yemeni Socialist Party - Abdul Fattah Ismail faction (YSP – AFI) in 1986, after President Ali Nasser Mohammed had attempted to assassinate several rivals within the YSP. Despite lasting only eleven days, the conflict was fought with extreme ferocity and would have far reaching consequences by solidifying intra-southern divisions. Both factions represented different parts of South Yemeni society, and was dominated by different tribal factions. The YSP – Abdul Fattah Ismail faction, often known as the Toghma (meaning 'ruling clique'), emerged victorious, though Ismail himself died during the conflict. Instead Ali Salem al-Beidh rose to power. Al-Beidh paved the way for the peaceful reunification with North Yemen in 1990, with al-Beidh becoming vice president of the unified state. Many of the survivors of the opposing faction, often derogatorily called the Zumra faction, had fled to the North, and was integrated into the North Yemen army as the Unity Brigades prior to unification.
Four years after unification a secessionist movement, the Democratic Republic of Yemen, unsuccessfully attempted to re-establish an independent South Yemen (see the Yemen: South Yemen conflict page). The uprising was led by the last leader of South Yemen and thereafter vice president of the united Yemen, Ali Salem al-Beidh. After a short war, the movement was defeated by the Government of Yemen in July 1994. The 1994 breakaway attempt was defeated in part by the losers of 1986, the Zumra survivors that became the Unity Brigades. Leading the return of the Zumra was Abdrabuh Mansur Hadi, who would later become vice-president under Saleh and president of Yemen in 2012 after Saleh was deposed. Power in southern Yemen was thereafter monopolized by the so-called Zumra, who made sure to keep the former Toghma affiliates out of positions of power and thus outside of the state-sponsored patronage network.
Southern separatism has occasionally flared since, often driven by the marginalized sections of South Yemeni society that aligned first with YSP – AFI in 1986 and with the Democratic Republic of Yemen in 1994. For instance, the loosely organized Southern Movement was engaged in occasional clashes with government forces since 2009, and supporters of the movement coalesced into the Southern Transitional Council (STC) in 2017. STC has mainly fought as part of Forces of the Presidential Leadership Council (pre-2022 called Forces of Hadi), and only briefly became active in the South Yemen conflict after STC splintered from the Presidential Leadership Council in 2025. The STC has repeatedly been engaged in non-state violence with the Forces of the Presidential Leadership Council since 2018. As a result of these internal conflicts, STC had managed to establish control over essentially all territories that had been part of South Yemen by the end of 2025, formally declaring the independence of the 'State of South Arabia' on 2 January 2026. The rapid expansion of STC on Saudi Arabia's border sparked a strong response, with Saudi Arabia launching airstrikes in support of PLC forces in December and January. Alongside political pressure that caused severe defections from within the STC, Saudi Arabia successfully instigated the rapid collapse of the STC, which in a month went from controlling half of Yemen to being little more than an rural insurgent group in Dali and Lahij governorates.
Since 1946 South Yemen has experienced the extra-state, interstate and intrastate categories of UCDP organised violence.
