King Cheng of Zhou in the context of "King Wu of Zhou"

Lu (Chinese: 魯; c. 1042 – 249 BC) was a vassal state during the Zhou dynasty of ancient China located around modern southwest Shandong. Founded in the 11th century BC, its rulers were from a cadet branch of the House of Ji (姬) that ruled the Zhou dynasty. The first duke was Boqin, a son of the Duke of Zhou, who was brother of King Wu of Zhou and regent to King Cheng of Zhou.

Lu was the home state of Confucius as well as Mozi, and, as such, has an outsized cultural influence among the states of the Eastern Zhou and in history. The Annals of Spring and Autumn, for instance, was written with the Lu rulers' years as their basis. Another great work of Chinese history, the Zuo Zhuan or Commentary of Zuo, was traditionally considered to have been written in Lu by Zuo Qiuming.

Dan, Duke Wen of Zhou, commonly known as the Duke of Zhou, was a member of the royal family of the early Zhou dynasty who played a major role in consolidating the kingdom established by his elder brother King Wu. He was renowned for acting as a capable and loyal regent for his young nephew King Cheng, and for successfully suppressing the Rebellion of the Three Guards and establishing firm rule of the Zhou dynasty over eastern China. He is also a Chinese culture hero, with the authorship of the I Ching and the Classic of Poetry having traditionally been attributed to him, as well as the establishment of the Rites of Zhou.