The structure of Yüan government took shape during the reign of Khubilai, and the essential components of the government bureaucracy that formulated under him remained intact until the end of the dynasty in 1368. The strongest Chinese influence at Khubilai's early court came from Liu Ping-chung, a Ch'an Buddhist and confidant of the Mongolian emperor. It is clear that separate civil and military bureaucracies existed, though there also is evidence that military officials did not always refrain from meddling in civilian affairs, and vice versa. Originating as a tribal, military society, the pastoral nomadic Mongols of the early and mid-thirteenth century evidenced little social stratification. Although the thirteenth-century Mongols did indeed have slaves usually non-Mongolian war captives rather than indigenous slaves it would not be correct to describe slave holding as a fundamental characteristic of the Mongols' tribal and clan-based pastoral nomadic society and economy. Yüan government and society reflect both continuities and breaks with the Chinese past.