[Time frame and reasons of Kangxi Emperor adopted variolation].

This paper is concerned with the time frame and the reasons why the Kangxi Emperor adopted variolation in the Qing Imperial family. The Manchus, especially the Qing Imperial family, lived in the fear of contracting smallpox. They took various strategies to protect themselves from smallpox. One of the most conspicuous methods was adopting variolation in royal family in the Kangxi reign. The purpose of this important action was to maintain the superiority of the Manchu minority and to reduce the mortality rate of smallpox in the Imperial family. In this paper, I would like to point out the time when the Kangxi Emperor intended to use variolation was earlier than we had known through the previous studies. The Emperor's decision of variolation was mainly stimulated by his personal experiences and his practical character.