This dyad belongs to the conflict Yemen (North Yemen): South Yemen
Summary of conflict Yemen (North Yemen): South Yemen
The Republic of Yemen was founded in 1990 when North Yemen and South Yemen (at times also called South Arabia) merged into one country. The armies and administrations, however, remained separated and a dispute in the new government eventually led to an attempted secession by the southern parts of the country in April 1994. The secession was hindered by the northern army which seized full control over the southern parts in July 1994. Although the violence was halted in 1994, southern national sentiments have remained.
In 2007 the avowedly non-violent Southern Movement emerged as a loose umbrella organization for groups supporting southern independence. It was largely involved in protests for southern issues and independence, some of which faced a violent response by security forces. Occasional clashes between armed factions within the Southern Movement and security forces erupted over the next decade, though no individual faction passed the threshold for inclusion.
In 2017, the Southern Transitional Council (STC) was formed by factions within the Southern Movement, and gradually consolidated its hold of the territories of that had belonged to South Yemen. Ansarallah (commonly known as the Houthis) had taken control of the capital, Sanaa, in January 2015, thus becoming the government according to UCDP definitions. Southern Yemen was under control of the Forces of the Presidential Leadership Council (formerly Forces of Hadi), which continued to be widely recognized as the legitimate government of Yemen. STC fought several rounds of conflicts with the Forces of the Presidential Leadership Council starting in 2018, generally reaching an agreement to rejoin the administration after having expanded their own territorial control. After a renewed uprising by STC in December 2025, STC was in full control of essentially all areas that had belonged to South Yemen, and declared itself independent on 2 January as the 'State of South Arabia'. During the December uprising, STC also fought with the Ansarallah government along its shared frontlines, activating the South Yemen conflict for the first time since 1994.
The unification of the Republic of Yemen
The unified Republic of Yemen was founded on 22 May 1990 when the Arab Republic of Yemen (North Yemen) merged with the People’s Republic of Yemen (commonly known as South Yemen, or as South Arabia among modern separatists). North Yemen had been part of the Ottoman Empire since the 19th century, while South Yemen had become a British colony during the same century. Following the end of the First World War, North Yemen gained independence, whereas South Yemen remained under British administration until 1967. During the Cold War, the northern part was more pro-western, while the south had become a pro-Soviet Marxist state. The relations between the two countries were tense at several times and border conflicts took place in 1972 and 1978-1979. After the end of the Cold War, Soviet’s support to the south declined and there was an interest from both sides to unite Yemen. The Parliaments of southern and northern Yemen elected Ali Abdullah Saleh, former President of North Yemen as President, and Ali Salim al-Beidh, former leader of South Yemen, as Vice-President.
Clashes between the North and the South of Yemen
The northern and southern armies, security forces and civil services bureaucracies had however remained completely separate after the unification, except for the exchange of the positions of a few military units. When a dispute between the President and the Vice-President and the Minister of Defence, both of which were former southern officials, was fueled by political assassinations the situation became highly volatile due to these separated armed forces.
The southern parts of Yemen’s Cabinet moved to the southern area Aden and negotiations between the parties to solve the crisis were held around January 1994. The parties to the negotiations were representatives of the members of Yemen's ruling coalition: Saleh's General Peoples Congress (GPC), al-Beidh's Yemeni Socialist Party (YSP) and the Yemeni Reform Group (al-Islah). Although President Saleh and Vice-President al-Beidh both supported the agreement that followed the talks, neither had signed it before the situation escalated to armed confrontations. Following violent clashes, the Democratic Republic of Yemen was proclaimed in the south on 21 May 1994. The Democratic Republic of Yemen existed until 7 July 1994 when the leadership of southern Yemen fled the country as the last piece of territory under their control fell to the northern forces.
The pro-North President Saleh had supported Iraq after his invasion of Kuwait, a service that was reciprocated by Iraq during the war with South Yemen as Iraq reportedly supplied the North with military hardware. Saudi Arabia, in turn, supported the South with military material.
There were a number of mediation attempts made by the Arab League, France, Russia, the Red Cross, the UN and the US. The United Nations launched two resolutions that called for a cease-fire. Both parties also announced unilateral truces on many occasions. All cease-fires failed within hours. The parties negotiated an the end of the war when the South was loosing territory, but the swift northern advance meant that the negotiations only dealt with the terms of surrender.
Return of Southern separatism after 1994
Despite the end of the armed clashes in 1994, the nationalist sentiments in the South have remained. People in the southern parts of Yemen often claim that they are being socially and economically marginalised by the northern parts of the country. The oil, which is Yemen’s primary source of income, is mainly located in the southern parts and it has repeatedly been argued by the southern parts that they don’t receive their perceived fair share of the revenue.
The 1994 breakaway attempt was defeated in part by a South Yemeni faction of the YSP, commonly called the Zumra, which had fled to the north after their defeat in the South Yemen civil war in 1986, and had been integrated into the North Yemen army as 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 affiliates of al-Beidh (known as the Toghma) out of positions of power and thus outside of the state-sponsored patronage network. Both factions represented different parts of South Yemeni society, and was dominated by different tribal factions, leading to future southern separatism largely being driven by the marginalized sections of South Yemeni society that had aligned with the Toghma.
In 2007 the avowedly non-violent Southern Movement emerged as a loose umbrella organization for groups supporting southern independence. Among its most prominent leaders was the exiled Ali Salim al-Beidh, former leader of South Yemen and Vice-President of the unified Yemen. The Southern Movement was largely involved in protests for southern issues and independence, some of which faced a violent response by security forces. During 2009, violence erupted in connection to several demonstrations held by the Southern Movement. Several people died during, and in connection to, the demonstrations, some in one-sided violence by security forces, some in violent political protests and some in outright armed clashes by militias connected to the Southern Movement.
Ansarallah (commonly known as the Houthis) took control of the capital, Sanaa, in January 2015, thus becoming the government according to UCDP definitions. It thereafter launched an attempt to take control of southern Yemen from the loose coalition supporting the internationally recognised president of Yemen at the time, Mansour Hadi (originally called Forces of Hadi, but later renamed Forces of the the Presidential Leadership Council). Southern militias emerged to oppose the Ansarallah takeover of the south, as part of the pro-Hadi coalition. Ansarallah was a Zaydi Shia fundamentalist movement, and was therefore viewed with deep suspicion by the mostly Sunni south. These militias coalesced into the Southern Transitional Council (STC). When STC was formed on 11 May 2017, it stated that its goal was to form of an independent southern state with the pre-1990 borders, consisting of the governorates of Aden, Lahij, the southern part of al-Dhali, Abyan, Shabwa, Hadramawt, al-Mahra and Socotra. When it formally declared independence on 2 January 2026, it did so as the 'State of South Arabia', a name preferred by some nationalists as an alternative to South Yemen. STC received considerable support from the United Arab emirates (UAE), which helped build it into one of the strongest factions in Yemen's multifaceted civil war.
STC fought several rounds of conflicts with the Forces of the Presidential Leadership Council starting in 2018. After each round of conflict in 2018, 2019 and 2020, a new agreement to rejoin the Hadi administration was reached. Each round of conflict resulted in STC expanding their own territorial control at the expense of the Forces of Hadi. Notably, in 2018, STC took control of Aden, the former capital of South Yemen and the interim capital of the Hadi government during its exile from Sanaa. As the Hadi government was a non-state actor according to UCDP definitions, the conflict for South Yemen was never active.
The STC was a founding member of the Presidential Leadership Council (PLC) in April 2022, an eight-man council which replaced Hadi as the presidential authority in the internationally recognized government. As a core part of the movement, it was able to deal with rivals in the PLC without intervention by any central authority, allowing it to expand its control over much of South Yemen.
Renewed conflict in 2025
After a renewed uprising by STC in December 2025, STC was in full control of essentially all areas that had belonged to South Yemen, and declared itself independent on 2 January as the 'State of South Arabia'. During December, it continued to clash with the Ansarallah government of Yemen along its shared frontline, resulting in the South Yemen conflict becoming active for the first time since 1994. Saudi Arabia directly intervened in support of the PLC, launching a campaign of airstrikes against the STC in late December and January. In combination with the strikes, intense Saudi diplomatic pressure on factions within the STC caused it to fracture, with several factions defecting to the PLC. The STC's resistance rapidly collapsed, with its leader reportedly fleeing to UAE as PLC forces entered Aden on 7 January, facing only limited resistance.
