(Al Jazeera) – In 2015, Yemeni President Abd-Rabbu Mansour Hadi established his government in the southern city of Aden after being forced by Houthi rebels to flee the capital, Sanaa. As the threat of the rebels grew, southern forces closed ranks around Hadi to defend the coastal city and other areas in the south with the support of a military coalition led by Saudi Arabia. However, from the very beginning, this was a forced alliance in a region where separatist feeling prevailed even before the war. The south was an independent state until unification with the north in 1990.