"Zhou Dynasty"
Wu Zetian proclaimed herself as the ruler of the "Zhou Dynasty", and from 690 to 705 the Chinese Empire was known as the Zhou Dynasty. However, the traditional historical view is to discount Wu's "Zhou Dynasty": dynasties by definition involve the succession of rulers from one family: Wu's "Zhou Dynasty" was founded by her, and ended within her lifetime, with her abdication (705). This does not meet the traditional concept of a dynasty. The alternative, is to view Wu's "Zhou Dynasty" as the revival of the generally historically accepted Zhou Dynasty (1046–256 BC), which had been ruled (at least nominally) by the Ji family, almost a thousand years before. Either way, Wu's Zhou Dynasty is best viewed as a brief interruption of the Li family's Tang Dynasty, rather than as a fully realized dynasty. Her claim of founding a new dynasty, however, was little opposed at the time (690). The 15 year period which Wu Zetian designated as her "Zhou Dynasty" considered in the context of nearly a half century of de facto rule (ca. 654–705) reveals a remarkable and still debated period of history. In this context, designating a new dynasty, with herself as its emperor can be seen as part of her power politics, and the Zhou Dynasty of Wu Zetian did have its notable characteristics, as the culmination of her period of ruling. The 15 years of her Zhou Dynasty had its own characteristics, however these are difficult to really separate from the reign of power of Wu herself, which lasted for about half of a century.
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