Linghu Defen - During Emperor Taizong's Reign

During Emperor Taizong's Reign

In 629, during the reign of Emperor Gaozu's son Emperor Taizong, Emperor Taizong was interested in the compilation of the histories, and he therefore issued an edict commissioning Linghu Defen and Cen Wenben to compile the history of Northern Zhou (Book of Zhou); Li Baiyao to compile the history of Northern Qi (Book of Northern Qi); Yao Silian to compile the histories of Liang (Book of Liang) and Chen (Book of Chen); and Wei Zheng to compile the history of Sui (Book of Sui), and to oversee the overall compilation project with Fang Xuanling. These officials also convened to discuss the issue of the history of Northern Wei, but concluded that as Northern Wei's history has already been compiled in the past by Wei Shou (now known as the Book of Wei) and Wei Dan (魏澹, Wei Shou's cousin, who compiled a separate Book of Wei now no longer extant), it was no longer necessary to have a new compilation. At Linghu's suggestion, the imperial censor Cui Renshi was also invited to join the Northern Zhou project, and Linghu himself also contributed to the compilation of the histories of Liang, Chen, Northern Qi, and Sui. Later historians praised Linghu for spearheading the overall project.

In 632, Linghu was made the deputy minister of rites (禮部侍郎), but continued to serve as an imperial historian. He was also created the Baron of Pengyang.

In 636, the Book of Zhou was completed, and Linghu was awarded silk.

In 637, another work by Linghu, the New Rites (新禮), was completed, and his title was promoted to Viscount of Pengyang. Also that year, another project that Linghu participated in, the Records of Clans (氏族志), was completed as well, and he was awarded silk again.

In 641, Linghu was made a member of the staff of Emperor Taizong's son Li Chengqian the Crown Prince. In 643, after Li Chengqian was deposed, Linghu was relieved of his duties.

In 644, Linghu was recalled to civil service and made the prefect of Ya Prefecture (雅州, roughly modern Ya'an, Sichuan), but was later removed from office due to his acts there. Soon, however, when Fang was put in charge of compiling the history of Jin Dynasty (265-420) (Book of Jin), Linghu was made the lead editor on the project, which involved 118 editors, and the other editors largely followed Linghu's lead. After the work was completed in 648, Linghu was made Mishu Jian (秘書監), the head of the archival bureau.