Peter Lorge, in Reunification of China: Peace through War under the Song Dynasty, describes the major campaigns in the second half of tenth-century China in order to explore the influences and historical meanings behind these battles. He provides a revision to the standard interpretation of the Northern Song founding, which had been characterized as a watershed in launching a period of civilian dominance by shifting political power from the generals to civil officials. The author argues that China's return to reunified empire was a long process filled with chaotic events and uncertainty lasting from the Gaoping Campaign in 954 to the Chanyuan Campaign in 1004, and that the establishment of civil dominance in the eleventh century was far from the product of imperial design. Because military feats were important to imperial authority and dynastic survival, generals retained their power and influence through the early Song, until the Chanyuan Covenant produced a long-term peace. Song armies were highly effective in the field, the author argues, so the Song civil culture had yet to flourish at the expense of the military. The perception that Song leaders adopted policies unfavorable to the military from the dynasty's very outset is likely a legend created by later literati, not historical fact.

By underestimating the achievements of previous regimes, Song literati glorified the Song founders. The fact that Peter Lorge starts his book with the Later Zhou dynasty and spends two chapters discussing the accomplishments of Emperor Zhou Shizong reflects the fact that the new epoch actually began in the Later Zhou, which is traditionally considered the final regime of the Five Dynasties period. The chapters about the rule of Zhou Shizong and Song Taizu show that Song Taizu followed Zhou Shizong's policies in almost every field. Thus, Song Taizu did not revolutionize dynastic institutions or traditions, though that was the image that Song literati created for their founder. To prove that the Song founder lacked a clear blueprint for building his regime, Peter Lorge refutes the traditional explanation for the reunification of China, which portrayed Song Taizu as following Zhao Pu's “south first strategy” to conquer the southern kingdoms before launching expeditions against the north. Based on solid evidence, Lorge's research demonstrates that Zhou Shizong and Song Taizu actually preferred an opportunistic approach to the border and intended to maintain strategic flexibility, rather than follow any prescribed strategy. Zhao Pu's proposal actually failed to play an important role in the reunification.

Besides narrating military and diplomatic actions, this book also explores political developments in the early Song, focusing on the struggles between Emperor Song Taizu, Zhao Pu, and Taizu's brother Zhao Kuangyi. The leading obstacle to analyzing the issue in any depth is the dearth of reliable sources. For example, Zhao Kuangyi clearly accumulated significant personal power and built his own networks during Taizu's reign, which enabled him to finally succeed to the throne in 976. However, we have very little material documenting what Zhao Kuangyi actually achieved in Taizu's reign beyond a list of titles. As Taizu's management style was very personal, the position officials held rarely reflected their true power or influence. Thus, historians lack enough evidence to evaluate Zhao Kuangyi's role during his brother's reign. Moreover, some tales related to Taizu's rule were myths created by later literati, who usually conflated historical events with their personal opinions. On pages 178–79, for example, Lorge cites a story about Zhao Kuangyi's opposition to his brother's proposal to move the capital to Luoyang as evidence of their close relationship. In that story, Taizu predicted that the huge expense of provisioning soldiers would exhaust government finances in the future, but the unbridled expansion of the armies did not occur in Taizu's period. How could Taizu anticipate a future financial crisis based on the numbers at the time? It is highly likely that later Song literati, witnessing the financial problems unfold, fabricated the prediction, so the entire story is problematic, along with assumptions based on it. Use of this sort of problematic material weakens the author's case for revising early Song political history.

As the author notes, military history has not been an important field for historians of Song China, especially among western academics. For this reason, Lorge pays special attention to introducing and critically analyzing the Chinese secondary scholarship, and contrasts Chinese scholarship with American approaches. For the western reader, his book seeks to provide knowledge about the process by which China was reunited in the tenth century as an historical event, while helping them to understand something about the historiography of Song studies in both Taiwan and mainland China. Unfortunately, his book fails to include a glossary and Chinese appear only in Hanyu pinyin, so the names of scholars who use other systems of romanization might be confused.

Building on previous scholarship, this book outlines in detail the process by which the Song was founded from a military perspective. The next task for military historians of the tenth century would be to undertake more analytic and synthetic research. Peter Lorge mentions at least twice the limited military resources available to early Song emperors, which he uses to explain Song Taizu's conquest strategy and the military stalemate between Song and Liao in the late Taizong period (128, 225). However, he fails to analyze in any detail how limited resources set the parameters for government policy. Analyzing military resources in Song times requires both substantial and intellectual perspectives, I would argue. In terms of resources, we should estimate not only the number of trained soldiers and talented commanders, but also the financial resources and logistical management abilities available to the Song government. Then we need to ask to what degree was the government constrained from investing its substantial resources into military campaigns because of the attitudes of the Song political elite, including bureaucrats and generals. If the elites did not favor bellicose policies or lacked confidence in their armies, the emperor would lack support to launch military actions. Thus, the intellectual factors might present significant limitations to the use of military resources, and military historians need to pay attention to the intellectual world of the period they study.