Sòng Rénzōng 仁宗 (Zhào Zhēn 趙禎, 1010–1063), the fourth Northern-Sòng emperor (r. 1022–1063), the longest-reigning of the Northern Sòng. The son of Zhēnzōng 真宗, his reign was the political and cultural high-point of the Northern Sòng — the era of the Qìnglì 慶曆 reform, of Fàn Zhòngyān 范仲淹, Ōuyáng Xiū 歐陽修, Sū Shùn 蘇舜, the early careers of Wáng Ānshí 王安石 and Sīmǎ Guāng 司馬光, and the comprehensive reorganisation of the Northern-Sòng bureaucracy and Buddhist institutions.
In matters Buddhist he composed the Yùzhì fóyá zàn 御制佛牙贊 (Imperially Composed Encomium on the Buddha’s Tooth), one of three imperial encomia later combined into the 1065 stele Sāncháo yùzhì fóyá zàn — the original of the Dàzú stone-inscription KR6v0049. A Dūnhuáng witness of his verses survives independently as S. 4358 (titled Lǐ xiānggōng tàn zhēnshēn 李相公歎真身).