Arnuwanda Ii in Wikipedia
Arnuwanda II was a king of the Hittite Empire (new kingdom) ca. 1322–1321 BC (short chronology). He succeeded his father Suppiluliuma I, who succumbed to the plague which Egyptian captives from his Canaan campaign had brought with them to the Hittite heartland.
Later Hittite documents reveal that Arnuwanda had also caught this plague. His younger brother Mursili helped him with Hatti's ongoing struggles against the Kaska and Arzawa lands. In one such event, the brothers wrote to Karkiya that they provide asylum to Manapa-Tarhunta of Seha River, who had been ousted in a coup. As a result, Manapa-Tarhunta was able to return to Seha River as its leader. (Unfortunately Manapa-Tarhunta proved faithless anyway a few years later.)
Arnuwanda eventually died of the plague and was succeeded by his brother Mursili II. While Arnuwanda II had long been groomed by Suppiluliuma I, to be the latter's successor and was respected by Hatti's enemies, Mursili is stated in the Hittite records to be relatively young and inexperienced upon his unexpected accession to the throne.