Wu Zetian
Reign as empress regnant

In 690, Wu had Emperor Ruizong yield the throne to her and established the Zhou dynasty, with herself as the imperial ruler (Huangdi).

The early part of her reign was characterized by secret police terror, which moderated as the years went by. On the other hand, she was recognized as a capable and attentive ruler even by traditional historians who despised her, and her ability to select capable men to serve as officials was admired for the rest of the Tang dynasty as well as in subsequent dynasties.

Wu Zetian's reign was a pivotal moment for the imperial examination system. The reason for this was because up until that point, the Tang rulers had all been male members of the Li family. Wu Zetian, who officially took the title of emperor in 690, was a woman outside the Li family who needed an alternative base of power. Reform of the imperial examinations featured prominently in her plan to create a new class of elite bureaucrats derived from humbler origins. Both the palace and military examinations were created under Wu Zetian which were based solely on merit.
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