690 CE
A year defined by Wu Zetian's formal assumption of the title of emperor in China, becoming the only woman in Chinese history to rule as emperor in her own right.
Geopolitics & Diplomacy
- Wu Zetian formally proclaimed herself Emperor of China, establishing the brief Zhou dynasty and becoming the only woman in Chinese history to hold the title of emperor regnant.
- Wu Zetian had already been the de facto ruler of China for years, having wielded power as empress consort and then empress dowager, systematically removing rivals and consolidating control.
- Her reign continued many of the administrative and military policies of the Tang dynasty she had supplanted, including the expansion of the civil service examination system to broaden the base of government officials.
Culture & Society
- Wu Zetian was a patron of Buddhism and commissioned major Buddhist artistic and architectural projects, including additions to the Longmen Grottoes near Luoyang.
- The estimated world population was approximately 217 million.
Climate & Environment
- Atmospheric carbon dioxide concentration was approximately 277 parts per million, as later confirmed by ice core analysis.