As the title says I can't get any story to start with Arthas when I go through the Reign of Chaos bookmark. I thought this would be the the proper start point for the Arthas storyline but it didn't happen. The only story point that occured was Jaina asking me to sail to Kalimdor with her and if I go, then nothing further happens with the story and Jaina married a tauren?... if I stay in Lordaeron then I eventually just die and become a random undead.

I remember doing this years back and Arthas went on a pilgrimage, acquired Frostmourne, became a death knight... why isn't this happening?

EDIT: I can see the event chain happen for either Arthas or Calia if I play as a custom character but when I play as one of them it doesn't happen. That's weird.

EDIT 2: Figured it out. All I had to do was make sure the character I'M playing is the heir to the High Kingdom of Lordaeron.