The task given to him by the Arcadian King was to settle conflict within the more problematic regions of the kingdom, as well as becoming a good mayor.
In terms of reducing conflict, at the very least Tristan was able to settle the town's problems with the barbarians and create a sense of order as well.
As for the sudden death of the previous mayor, although it happened immediately after the quest was assigned, he assumed that the king would still pin the issue on him and have it added to his already long list of responsibilities.
Tristan was still waiting for more information regarding the matter, hoping that at least one of his citizens would have any leads, but unfortunately there were none. He could only hope that either Chieng or his wife would bring back new information soon.
Next, there was the problem with the orc attacks that Tristan had to handle as well.