Neo-Confucianism is the English reference to the revival of Confucian religious, social, and ethical thought that eventually dominated Chinese official culture from the 13th through the 19th century. As early as the 9th century, there was a renewed interest in Confucianism, which had been eclipsed by Buddhism for roughly seven hundred years. At its core, Neo-Confucianism focused on the works of the Classical Confucian tradition (particularly Confucius’s Analects, the Mencius, and selected chapters from the Book of Rites) as a means of ordering human society. To this was added a metaphysical argument affirming the ultimate reality of the world, which responded to the Buddhist assertion (overly simplified by their Neo-Confucian detractors) that this world is illusion. From this affirmation, Neo-Confucians developed integrated social, political, and philosophical systems pointing toward the individual’s obligation to find the appropriate role within these overlapping systems and thereby contribute to universal harmony. Through the process of self-transformation, one hoped to become a sage: a moral, social, and political paragon. The core Neo-Confucian ideas were developed in the 11th and 12th centuries by a number of different thinkers. There were diverging selections of core texts to study, competing interpretations of Classical Confucian texts, and wide-ranging debates about the role of Neo-Confucians in society and politics. In the 12th century, Zhu Xi streamlined the tradition. He is considered the great synthesizer of Neo-Confucian thought. It is his vision of the Confucian tradition that eventually became state orthodoxy in the 13th century. Anyone who hoped to become a scholar-official in Late Imperial China had to spend years studying and memorizing the core texts and commentaries as collated and written by Zhu Xi. Challenges to Zhu Xi’s orthodoxy arose in later periods, particularly in the Ming dynasty with Wang Yangming; but no alternative fully displaced Zhu Xi’s orthodox status within the official examination system. In 1905, Neo-Confucianism was decoupled from the examination system. In the 20th-century drive to modernize, many criticized Neo-Confucianism as a force that held China back. Still, others, particularly outside the People’s Republic of China, continued to see value in the tradition and developed post-Imperial “New Confucianism.” Since the 1980s, interest in Confucianism has revived in the PRC as well.