Du Bo was the Duke of Tangdu (唐杜公) in the reign of Zhou Xuan Wang

King Xuan of Zhou

King Xuan of Zhou was the eleventh sovereign of the Chinese Zhou Dynasty. Estimated dates of his reign are 827-782 BC or 827/25-782 BC.He worked to restore royal authority after the Gong He interregnum. He fought the 'Western Barbarians' and another group on the Huai River to the southeast. In...

 (827 – 781 BCE).

Background

According to legend, the Tangdu were descendents of the people who lived in the State of Tang, a Dukedom situated to the west of the State of Yi in Shaanxi

Shaanxi

' is a province in the central part of Mainland China, and it includes portions of the Loess Plateau on the middle reaches of the Yellow River in addition to the Qinling Mountains across the southern part of this province...

 province. This Dukedom was annihilated by Zhou Gong Dan

Duke of Zhou

The Duke of Zhou played a major role in consolidating the newly-founded Zhou Dynasty . He was the brother of King Wu of Zhou, the first king of the ancient Chinese Zhou Dynasty...

 (Duke of Zhou), but his nephew Zhou Cheng Wang allowed the Tang to form a new State of Du, and became known as Tangdu or Du Shi (杜氏).