Japan's sixteenth-century unification, as it was both observed by Europeans and influenced by the introduction of Western arms, has naturally suggested to historians various points of comparison between European and Japanese historical institutions. Japan during the sixteenth and seventeenth centuries underwent several similar political and social changes. The country achieved a new degree of political unity. The Tokugawa hegemony gave rise to a highly centralized power structure, capable of exerting nationwide enforcement over military and fiscal institutions. Daimyo were permitted to retain their own armies and also a considerable amount of administrative autonomy. This chapter discusses the Ōnin-Bummei War of 1467 to 1477 that marked the beginning of the final downward slide of the Muromachi shogunate. The victory of Tokugawa Ieyasu's forces against the Toyotomi faction at the battle of Sekigahara in 1600 marked the beginning of the Tokugawa hegemony.