After Li Jipeng (aka Zhao Baozhong), a Tangut prince who had submitted to the Song dynasty, raided Xia's territory and destroyed some fortified settlements in 1034, the Tanguts under Li Yuanhao (1003–1048) retaliated. On 12 September 1034 the Tanguts raided Qingzhou in Huanqing Circuit, but later Li Yuanhao released Song officers and soldiers he had captured; by 29 January 1035 relations were restored when Li Yuanhao sent tribute of fifty horses to the Song court and requested a copy of a Buddhist canon in return, which he received. Although he retained some unique Tangut customs and had a Tangut script created, Li's administration followed the traditional Chinese model of bureaus. Li proclaimed himself the first imperial ruler of Western Xia, ruling as Emperor Jingzong (r. 1038–1048), and on 10 November 1038 he sent an envoy to the Song capital in order to gain recognition for his new title as "Son of Blue Heaven" and to cease paying tribute to Song to affirm his new status. The Xia began attacks on Song's borders which were repulsed by Song commander Lu Shouqin (fl. 1030–1050), and on 9 January 1039 the Song shut down its border markets and soon after a reward of 100,000 strings of coin was offered to anyone who could capture Emperor Jingzong. Although he won impressive victories in the initial phase of the war, Jingzong gained no additional territory for Western Xia by war's end in 1044, while both sides had lost tens of thousands of troops. Emperor Jingzong also conceded to the Song demand that he refer to himself as an inferior subject when addressing the Song, and that he accept Song ritualists to perform official ceremonies at his court. Throughout the war, the Song had maintained a number of fortified military outposts stretching some from the westernmost prefectures of Shaanxi to Hedong in what is now Shanxi. Since the Song could not rely on water obstacle defenses in this region—like the Great Ditch of Hebei used against Liao—they instead garrisoned the wide expanse with a recorded 200 imperial battalions and 900 provincial and militia battalions by 1043.