Dou Wei
Dou Wei was from Fufeng Commandery (扶風, roughly modern Baoji, Shaanxi). His father Dou Chi (竇熾) served as a high-level official for both Northern Zhou and Sui and was a hereditary noble. Dou Wei was considered quiet and studious in his youth, much unlike his brothers and cousins who, as nobles, were far more interested in military matters. The Sui official Li Delin knew of his talent and recommended him as a junior official at the Palace Library, but while it was regular for junior officials there to be promoted regularly, Dou was not promoted, and remained at his post for more than a decade, during which he studied the archives and became even more knowledgeable than before.