evidence: The Sung was unlike the Han and the T’ang in yet another way. The Sung had no trial run. Short-lived yet strong dynasties (the Ch’in, 221–207 bc, and the Sui, ad 581–617) had preceded both the Han and the T’ang. These dynasties, although brief, had accomplished military consolidation and laid down institutional and administrative frameworks that their successors readily adapted. The Sung founders were not so fortunate. Tenth-century Sung government was a hopeless patchwork of late T’ang administrative structure and ad hoc provincial institutions inherited from the military governors of the Five Dynasties. These facts explain much of the tentative nature of early Sung political life. There was constant tension between the need to keep old political institutions functioning and, simultaneously, the need to develop new institutions better suited to changing times.