In the early Đại Việt period (pre-1200), the Viet monarchy existed as a form of what historians describe as a "charter state" or a "mandala state." In 1973, Minoru Katakura used the term "centralized feudal system" to describe the Lý dynasty’s Viet state. Yumio Sakurai reconstructed the Lý dynasty as a local dynasty, that the dynasty was only able to control several inner areas, while outer areas (phu) were autonomously governed by local clans of various ethnolinguistic backgrounds, who aligned to the royal clan through Buddhist alliances, such as temples. The Viet king "man of prowess" was the center of the mandala structure that has influences beyond the Red River Delta via Buddhist alliance with local lords, while a bureaucracy was still practically nonexistent. For examples, an inscription dating from 1107 in Hà Giang records the religious-political connection between the Nùng Hà clan with the dynasty, or another inscription dated 1100 commemorates Lý Thường Kiệt as the lord of Thanh Hoá. As a mandala realm, according to F. K. Lehman, its direct territories could not exceed more than 150 miles in diameter, however, the Đại Việt kingdom was able to maintain a large influence sphere due to active coastal trade and maritime activities with other Southeast Asian states.