The nation of South Sudan was formed in 2011 due to the Arab-Muslims in what was northern Sudan violently persecuting Christian and animist blacks in what became South Sudan. South Kordofan is a province of Sudan that borders South Sudan, so it is possible that many residents are also Christian and/or animist and black and thus targets of the Arab-Muslim rulers of Sudan. Speculating further, the Arab-Muslim rulers of Sudan would also love to conquer South Sudan, and a bordering province would be a valuable base to launch an invasion.