During the 15th century, state-supported schools declined in quality and were supplanted in importance by private academies, the seowon, centers of a Neo-Confucian revival in the 16th century. Higher education was provided by the Seonggyungwan, the Confucian national university, in Seoul. Its enrollment was limited to 200 students who had passed the lower civil-service examinations and were preparing for the highest examinations.