Task: Question Generation
Input (English): Passage: Alodia, also known as Alwa (Greek: Aρουα, Aroua; Arabic: علوة‎, ʿAlwa), was a medieval Nubian kingdom in what is now central and southern Sudan. Its capital was the city of Soba, located near modern-day Khartoum at the confluence of the Blue and White Nile rivers.
Founded sometime after the ancient kingdom of Kush fell, in around 350 AD, Alodia is first mentioned in historical records in 569. It was the last of the three Nubian kingdoms to convert to Christianity in 580 following Nobadia and Makuria. It possibly reached its peak during the 9th–12th centuries when records show that it exceeded its northern neighbor, Makuria, with which it maintained close dynastic ties, in size, military power and economic prosperity. Being a large, multicultural state, Alodia was administered by a powerful king and provincial governors appointed by him. The capital Soba, described as a town of "extensive dwellings and churches full of gold and gardens", prospered as a trading hub. Goods arrived from Makuria, the Middle East, western Africa, India and even China. Literacy in both Nubian and Greek flourished.
From the 12th, and especially the 13th century, Alodia was declining, possibly because of invasions from the south, droughts and a shift of trade routes. In the 14th century, the country might have been ravaged by the plague, while Arab tribes began to migrate into the Upper Nile valley. By around 1500 Soba had fallen to either Arabs or the Funj. This likely marked the end of Alodia, although some Sudanese oral traditions claimed that it survived in the form of the kingdom of Fazughli within the Ethiopian-Sudanese borderlands. After the destruction of Soba, the Funj established the Sultanate of Sennar, ushering in a period of Islamization and Arabization.
Output (English): What likely marked the end of Alodia?