I'm interested in the historical person of Nicholas, not the legend of Santa Claus/its evolution (except for where it directly relates to him as a historical person).
Some stuff I'd be interested in:
Is his actual existence as a person in the 3-4th centuries widely accepted, or is there debate? What are some of the arguments/evidence on both sides?
What are the odds that the remains in Bari, Italy actually belong to Nicholas?
Was he actually at the Council of Nicaea?
Where and when does our information about Nicholas come from? If this is too broad, limit it to some of the most well-known or prominent info
What do we know about his time as bishop (or just his ministry in general)?
Please don't limit any answers just to my questions. They are more like guidelines :)
This thread and especially the links to the blog posts, should provide some of the best info I've been able to dig up.
In short, there is no particular debate about his existence, it's fairly likely based on the evidence that there was such a person.
There's not much evidence that he was at Nicaea, and the story of him slapping Arius appears to be entirely apocryphal and only appears in later sources.
Most of our info derives from popular 'Lives of the Saints' texts from later Byzantium. In Nicolas' case, most of it derives from two works, a vita by Michael the Archimandrite (probably early 9th century), and a vita by John Diaconus (ca. 880), everything else is mostly derivative/compiled.