out a series of reforms, from centralizing government, built the first extensive bureaucracy and strong fiscal system, institutionalizing education, trade, and laws. He greatly reduced the power of the traditional Buddhist aristocracy with a scholar-literati class, ushered a brief golden age. Classical scholarly, literature (in nom script), science, music, and culture flourished. Hanoi emerged as the centre of learning of Southeast Asia in the 15th century. Lê Thánh Tông's reforms helped heightened the power of the king and the bureaucratic system, allowing him to mobilize a more massive army and resources that overawed the local nobility and capable to expand the Việt territories. To expand the kingdom, Lê Thánh Tông launched an invasion of Champa in early 1471 that brought destruction to the Cham civilization and made the rump state Panduranga a vassal of Đại Việt. Respond to disputes with Laos over Muang Phuan and the mistreatment of the Laotian envoy, Lê Thánh Tông led a strong army that invaded Laos in 1479, sacked Luang Phabang, occupied it for five years, and advanced far away as Upper Burma. Vietnamese products, particularly porcelains, were sold throughout Southeast Asia, China, and also in modern-day East African coast, Japan, Iran and Turkey. Decline and disintegration In the next few decades after Lê Thánh Tông's death in 1497, Đại Việt once again fell to civil unrest. Agricultural failures, rapid population growth, corruption, and factionalism all compounded to stress the kingdom, leading to a rapid decline. Eight weak Lê kings briefly held power. During the reign Lê Uy Mục–known as the "devil king" (r. 1505–1509), bloody fighting ignited between the two rival Thanh Hoá families in the cadet branch, the Trịnh and the Nguyễn on behalf of the ruling dynasty. Lê Tương Dực (r. 1509–1514) tried to restore stability, but chaotic political struggles and rebellions returned years later. In 1516 a Buddhist-peasant rebellion led by Trần Cảo stormed the capital, killed the emperor, plundered, and destroyed the royal palace along with its library. The Trịnh and Nguyễn clans briefly ceased hostility for a short time, suppressed Trần Cảo, and installed a young prince as Lê Chiêu Tông (r. 1517–1522), then they quickly turned against each other and forced the king to flee. The chaos prompted Mạc Đăng Dung, a military officer and well-educated in Confucian classics, to rise up and try to restore order. By 1522, he effectively subjugated the two warring clans and put