The British, who had set up a protectorate area around the southern port of Aden in the 19th century, withdrew in from what became the People's Republic of Southern Yemen colloquially known as South Yemen. Three years later, the southern government adopted a Marxist orientation and changed the country's name to the People's Democratic Republic of Yemen. The massive exodus of hundreds of thousands of Yemenis from the south to the north contributed to two decades of hostility between the states.
The two countries were formally unified as the Republic of Yemen in A southern secessionist movement and brief civil war in was quickly subdued. In , Saudi Arabia and Yemen agreed to delineate their border. Fighting in the northwest between the government and the Huthis, a Zaydi Shia Muslim minority, continued intermittently from to , and then again from present.
The southern secessionist movement was revitalized in Public rallies in Sana'a against then President Ali Abdallah SALIH - inspired by similar demonstrations in Tunisia and Egypt - slowly built momentum starting in late January fueled by complaints over high unemployment, poor economic conditions, and corruption. By the following month, some protests had resulted in violence, and the demonstrations had spread to other major cities. In April , the Gulf Cooperation Council GCC , in an attempt to mediate the crisis in Yemen, proposed the GCC Initiative, an agreement in which the president would step down in exchange for immunity from prosecution.
SALIH's refusal to sign an agreement led to further violence. The UN Security Council passed Resolution in October calling for an end to the violence and completing a power transfer deal.
HADI concluded the NDC in January and planned to begin implementing subsequent steps in the transition process, including constitutional drafting, a constitutional referendum, and national elections. The Huthis, perceiving their grievances were not addressed in the NDC, joined forces with SALIH and expanded their influence in northwestern Yemen, which culminated in a major offensive against military units and rival tribes and enabled their forces to overrun the capital, Sanaa, in September He subsequently escaped to Oman and then moved to Saudi Arabia and asked the GCC to intervene militarily in Yemen to protect the legitimate government from the Huthis.
