Who caused the Black Years?

The Black Years was a global catastrophe that hit Salan almost 200 years ago. A volcano on Crescent Island erupted, causing a volcanic winter. In the aftermath the refugees also ended up spreading a deadly plague all around the world.
The knowledge of the actual cause of the catastrophe is currently unknown. The Farens called the plague the Zeribian plague for long, because they believd, or wanted to believe that it was only affecting the Zeribian people, and was caused by the demon worship they were practising (from the Farens' point of view). This name, and the discrimination it was causing, continued to be in use long after it was quite evident that Farens were affected by the virus too.
Another common belief is, that the inhabitants of the Crescent ended up angering the Gods, who sent the eruption and plague to destroy them. The refugees were commonly denied any help in many cities once it was realised that a plague seemed to be travelling with them. They began to be called Šiwke 'Black Sails' because of the bad omen their arrival had. However, the earliest mentions of the plague predate the Eruption by atleast couple of years, and it was known from other islands before Crescent. Blaming the Šiwke was an easy scape goat for the rest of the Zeribian nobles.
The refugees decided to take pride in this heritage of being the survivors of the disaster against all the odds. They continued keeping their heritage alive, and probably had a much clearer picture of what actually happened during the catastrophe than anyone else. The closest relatives of the past rulers presumably perished during the catastrophe, but they managed to keep alive the noble house. They remained relatively unknown until, after the Zeribian Revolution of Der Fem, Ûzeŋadise-bargwel Šiwke Gwelzuh became the Vizier of Der Fem.