This dissertation focuses on a critical factor in historical transformation of medieval China-the dilemma between war and peace. Not only does this dissertation provide a brief and comprehensive account on conflicts, battles, and treaties, but it observes the attitude toward violence and the track of searching peace during Tenth and Eleventh Century China as well. Borrowing the concept of peace by modern scholars studying grand strategy, strategic culture, and pacifism, I regard peace as realistic strategic option, institutionalized establishment, consent behavior mode, and multi-oriented culture. My discussion begins with the exhausting campaigns of the T'ang in Central Asia and the ensuing civil war during the Ninth and Tenth centuries, arguing the Sung non-active posture in external adventure as a conscious avoidance of excessive violence. The relative success of the Sung policy saw in the peace annexation of the Wu-Yueh Kingdom and the conclusion of the Peace of 1005 between the Sung and Liao with modest cost. In addition, the early Sung rulers firmly controlled the military machinery and prevented war-making by internal and institutional causes. Nevertheless, the existing institutionalized peace between the Sung and Liao did not create a norm of behavior and prevent violence proliferation. Unable to contain the Tangut expansionism, the Sung was compelled to reinstate aggressive grand strategy, relieving constrain on its war machinery. Strategic imperative stimulated career military service of the Sung civil officials and gave room to the voice of pragmatic expansionism. Sung military achievement culminated in the success of rearmament during the reform of Wang An-shih. However, the ensuing war eventually ravaged the Sung empire, its opportunity for a great leap toward a pre-modern world missed
