Dynasty of Japanese shoguns who ruled the country from 1600 to 1868, called the Edo period after the Tokugawa capital at Edo (modern Tokyo). Tokugawa Ieyasu founded the line when he accepted the title of shogun from the emperor in 1603, after pacifying the country in 1600, and law codes issued in his name in 1615 underpinned its structure. Most daimyo had sworn fealty to Ieyasu, and Tokugawa estates comprising a quarter of Japan's farmland made him effectively supreme daimyo. Tokugawa authority over other daimyo was consolidated by obliging them to leave wives and families as permanent hostages at Edo, and to attend the shoguns in the capital every second year. Though virtually unchallenged rulers within their estates, the daimyo held their lands in fief from the Tokugawa, who could (and did) confiscate them in punishment. The emperors lived in luxurious impotence in Kyoto, subsidized and monitored by the Tokugawa.
To preserve stability, society was formally divided into four classes- samurai, farmers, artisans, and merchants-and contact with the world beyond Japan heavily restricted. Coins, weights, and measures were standardized, road networks improved, and detailed legal codes and admonitions issued. The Tokugawa peace, and the constant traffic of rich daimyo to and from Edo, brought Japan unprecedented prosperity, making it one of the world's most sophisticated pre-modern commercial societies, but the resulting population boom outstripped natural resources, leading to endemic peasant unrest. Also, the rigid Tokugawa administration, which surrounded the shogun with ministers and advisers, impeded response to growing colonialist encroachment. Finally, pro-imperial radicals from remote daimyo domains in western Japan unreconciled to Tokugawa overlordship toppled the dynasty in the Meiji Restoration. The 15th Tokugawa shogun fell in 1868, and became a member of the new Meiji aristocracy.