Song-Yuan zizhi tongjian 宋元資治通鑑 "The Comprehensive Mirror to Aid in Government of the Song and Yuan periods" is a continuation to Sima Guang's 司馬光 (1019–1086) Zizhi tongjian 資治通鑑. Because Sima's book ends in the year 959, it was necessary to expand this famous history, so that the Song 宋 (960-1279) and Yuan 元 (1279-1368) periods were covered, too. There are two books of this title. One was written by Wang Zongmu 王宗沐, and one by Xue Yingqi 薛應旂.
Wang Zongmu 王宗沐 (1523-1591, courtesy name Xinfu 新甫, style Jingsuo 敬所) explains his principles for the compilation of his book, but in fact he does not meet his own standards because the source material he used is very poor. His 64-juan long book was therefore neglected by later scholars.
Xue Yingqi 薛應旂 (1500–1575) also wrote the books Sishu renwu kao 四書人物考, Jiazi huiji 甲子會記, Kaoting yuanyuan lu 考亭淵源錄, Xianzhanglu 憲章錄 and Fangshan wenlu 方山文錄. His 157-juan long chronicle was intended as an alternative to Shang Lu's 商輅 Tongjian gangmu xubian 通鑑綱目續編 (also called Xu Song-Yuan zizhi tongjian gangmu 續宋元資治通鑑綱目 or shortly Xu zizhi tongjian gangmu 續資治通鑑綱目), an earlier continuation of Zhu Xi's 朱熹 (1130-1200) Tongjian gangmu 通鑑綱目, a restructuring of the Zizhi tongjian.
Yet Xue Yingqi did not make use of many important historiographical sources, like the writings of Wang Cheng 王偁 (early 15th cent.), Li Tao 李燾 (1115-1184), Yang Zhongliang 楊仲良 (early 13th cent.), Xu Mengxin 徐夢莘 (1124-1207), Liu Shiju 劉時舉 (fl. 1244), Peng Baichuan 彭百川 (XXX???), Li Xinchuan 李心傳 (1167-1244), Ye Shaoweng 葉紹翁 (1194-?), Chen Jun 陳均 (early 13th cent.) or Xu Ziming 徐自明 (?-1220+). He also neglected the histories of the empires Liao 遼 (907-1125) and Jin 金 (1115-1234) that ruled over northern China, and did not make use of the tables and treatises in the official dynastic histories of the Song and Yuan dynasties. His description of regulations and administrative statutes is very short and most of the biographies not consistent enough. Sometimes two persons are described twice, with contradicting statements. He did not make text-critical research, and his book is quite unreliable, except the passages speaking about Neo-Confucian scholars.
The oldest print of Xue's book dates from 1626. Wang's book is included in the collection Zizhi tongjian daquan 資治通鋻大全. XXX Xue?