March 23—31, 1937: The Political Bureau of the CPC Central Committee holds an enlarged meeting in Yan'an, discussing the current domestic political situation and the tasks of the Party, focusing in particular on criticizing Zhang Guotao's mistakes

March 23, 1949: Mao Zedong leads the organs of the CPC Central Committee to leave Xibaipo for Beijing

March 23, 1961: The CPC Central Committee issues "a letter to the Central Office and Party Committees of all provinces, cities and districts on the need for serious investigation work," requiring central and local leaders at all levels to go conduct grassroots research, sum up both their positive and negative experiences and solve problems in their practical work