Who is the Duke of Zhou in Duke of Zhou?

Duke Zhou's name was Ji Dan (living about 1 100 BC), also known as Shu Dan, the fourth son of King Jichang of Zhou Wen and the half-brother of Ji Fa of Zhou Wuwang.

Confucius' dream of "I no longer dream of Duke Zhou" often appears in Confucianism. Duke Zhou is a frequent figure in Confucius' dreams. In China, where Confucianism has dominated the culture for a long time, Duke Zhou is inevitably directly associated with dreams. Dreams are often called "dreams of Duke Zhou" or "dreams of Duke Zhou".