Who am I, and where do I live?

Question

In the south of the north of the north

Lies a castle to which a king came forth

Amen to the prince who mourns

To whom the crown adorns

Who am I?

Hint:

The word Amen is more important than it may seem. It’s an abbreviation.

Hint 2:

The answer is a character of a video game.

Answer 1

You are

The Lich King (Warcraft Universe)

And you live in

The Icecrown Citadel, in the South of Icecrown (which is in the north of Northrend)
Amen is Arthas Menethil, a former prince or Lordaeron. He killed his father to become the king, found the cursed blade Frostmourne, and became the Lich King

Answer 2

Are you

Robb Stark from the book series A Song of Ice and Fire, who lived in Winterfell?

---

In the south of the north of the north

Winterfell is in the southern part of the nothern half of the North.

Lies a castle to which a king came forth

King Robert Baratheon visits Winterfell in the first book.

Amen to the prince who mourns

Robb's father, Ned, is executed in the final scenes of the first book.

To whom the crown adorns

Robb is later declared King of the North.

Answer 3

I think you are

Arthas Menethil (Warcraft 3)

In the south of the north of the north
Lies a castle to which a king came forth

Arthas went to Northrend, which is a quite chilly place

Amen to the prince who mourns

AMen = Arthas Menethil, mourns can be a reference to the cursed sword Frostmourne

To whom the crown adorns

He then becomes the Lich King