Considering Sauron's nine Nazgûl, the Witch-king of Angmar has always been the most trusted and powerful of the group. He stabbed Frodo with a Morgul-blade on Weathertop and destroyed Gandalf's staff during a scene in the movie The Lord of the Rings: The Return of the King. Despite his power and service to Sauron, very little is known about the Witch-king's life before the forging of the rings. In the videos and arictles to follow we will explore his background.
Video from The Red Book
"The first episode of this new Tolkien-focused Podcast relates to the development of the Witch-king of Angmar over the course of Tolkien's writings. Did you know that the Lord of the Nazgûl, the Witch-king, was once written as a Wizard from Númenor, of the same order as Gandalf? In this episode, I explore the development of this figure from the earliest drafts to the character we recognise today. Why did Tolkien make these changes? Does any part of Tolkien's original idea for this character remain in the finished tale?" from the video introduction
"In rode the Lord of the Nazgûl. A great black shape against the fires beyond he loomed up, grown to a vast menace of despair. In rode the Lord of the Nazgûl, under the archway that no enemy ever yet had passed, and all fled before his face."― The Return of the King, "The Siege of Gondor"
The Witch-king of Angmar was the chief of the Nazgûl, King of Angmar and Sauron's great captain in his wars. A wraith, the Witch-king of Angmar was nearly indestructible, a terrifying warrior, and a cunning strategist.
Some time after Sauron seized the Rings of Power in the Sack of Eregion, S.A. 1697 he gave nine of them to Mannish kings, sorcerers and other warriors.[1] With the power of their rings, the Nine achieved glory and grew wealthy, but they eventually started hating life as they were slowly drawn under Sauron’s dominion. In the end, they all became the dreadful Ringwraiths.
The one later known as the Witch-king[note 1] was a sorcerer,[2][3] probably[4] one of the unnamed three lords of Númenórean race, who accepted one of the Rings of Power.[5] He first appeared in the histories as a Ringwraith in S.A. 2251. Being the most powerful of the Nazgûl, he became their chief and the most feared servant of his master Sauron.
When Mordor fell in S.A. 3441, the Nazgûl vanished into the shadows and were not heard of again for a long time.[6]
Early power in Angmaredit
More than a thousand years later, in c. 1050 of the Third Age, Sauron began to rebuild his power in Dol Guldur. In c. 1300 his Nazgûl also reappeared and the Witch-king established his realm, Angmar, in the north.[6] His capital was Carn Dûm, on the northernmost peak of the Misty Mountains. He summoned men, orcs and other creatures of evil inclination to his banner. No one knew that he was actually a servant of the long-dormant Sauron and few that he was a wraith.[7]" from the article in Tolkien Gateway