Taira no Moritoki (Mandorkoro Chikeji [an official working under a director of the administrative bo (平盛時 (鎌倉幕府政所知家事))
TAIRA no Moritoki (year of birth and death unknown) was a bugyonin (government official for the bakufu, or feudal government head by a shogun) in the early Kamakura period. He is known as MINAMOTO no Yoritomo's yuhitsu (amanuensis, secretary).
He was commonly called 'Heigo.'
It is said that his official rank was Goi Minbu no jo (a fifth-rank official in charge of census and taxation).
When monchujo (a court of justice) was set up on December 1, 1184, he was appointed to be an assistant to MIYOSHI no Yasunobu, a betto (a supervisor).
From this, it is considered that he had already served Yoritomo at that time.
Together with OE no Hiromoto, Moritoki worked as a yuhitsu for Yoritomo.
When Hiormoto became busy with the duty of a betto at Kumonjo (administration office) and Mandokoro (administrative board), Moritoki himself drew up almost all important documents, such as migyosho (documents for informing of decisions made by third or upper ranked authorities) and hosho (a document for informing lower-rank people of the decision of upper people such as an emperor or shogun), although an additional yuhitsu, a substitute of Hiromoto, was supplemented.
Later, he was appointed as a Mandokoro Chikeiji in charge of the issue of bakufu's public documents.
When Yoritomo decided to track down and kill his younger brother, MINAMOTO no Yoshitsune, he sent a letter, in which he snapped angrily at gokenin (immediate vassals of the shogunate in the Kamakura period) in Kyoto (see the section Exclusion of Yoshitsune in 1185 in the page of MINAMOTO no Yoritomo).
It is said that this letter was written by Moritoki, who faithfully represented Yoritomo's opinions. In his 1186 letter addressed to Tsunefusa YOSHIDA, Kanto moshitsugi (court-appointed liaison with the Kamakura bakufu), Yoritomo said that he would autograph his Kao (written seal mark) for migyosho that were not written by OE no Hiromoto or TAIRA no Moritoki (to guarantee their authenticity). Two years later, Yoritomo also wrote to Tsunefusa, saying, "When I cannot finalize migyosho because of busy schedule, the validity of migyosho will be guaranteed with the Kao of OE no Hiromoto by proxy or the Kao of TAIRA no Moritoki as the second option." In other words, this suggests that in some cases, documents written by Moritoki or his Kao could guarantee equal authenticity as those of Yoritomo and of OE no Hiromoto, the head of Mandokoro. It is considered that this fact was recognized by the Imperial Court in Kyoto through Tsunefusa. From the history "Azuma Kagami" (The Mirror of the East), it is known that Moritoki assumed the post of kuji bugyonin (an official in charge of governmental affairs) by 1191, but it is considered that he continued to perform the duty of yuhitsu even in this period.
However, it is considered that unlike OE no Hiromoto, who directly got involved in governmental affairs, Moritoki acted rather as a personal secretary to Yoritomo.
It is confirmed that after Yoritomo's death, Moritoki continued to sit as a member of Mandoroko and served MINAMOTO no Yoriie and MNAMOTO no Sanetomo but was replaced by each master's aides later.
At that time, the number of articles on Moritoki's activities in"Azuma Kagami"--his activities are often recorded in the era of Yoritomo--plunged dramatically. Articles on Moritoki disappeared after the one dated March 30, 1212, and it seems that he passed away soon afterwards.