constant attacks by the armies of the Kingdom of Nanzhao (from present-day Yunnan). Nanzhao had just become a major military power in the region by defeating the Tibetan Empire in 801. The Nanzhao warriors then pressed down southward into the present-day Shan Hills and into the Irrawaddy valley. Ancient city-states one by one surrendered or were overrun by the "powerful mounted archers from the north". In 832, Nanzhao destroyed the city-state of Halin, close to old Tagaung, returning again in 835 to carry off many captives. The Nanzhao cavalry is said to have swept down all the way to the Bay of Bengal despite stiff resistance. Pagan period Following the Nanzhao raids, another Tibeto-Burman-speaking people called the Mranma (Burmans or Bamar), who had come down with the Nanzhao raids, began to settle the central Irrawaddy valley, near the confluence of the Irrawaddy and Chindwin rivers, en masse. The Burmans founded a small fortified city of Pagan (Bagan) c. 849, probably to help the Nanzhao pacify the surrounding country side. The early Pagan army consisted mainly of conscripts raised just prior to or during the times of war. The main weaponry of the infantry largely consisted of swords, spears and bow and arrows. The infantry units were supported by cavalry and elephantry corps. The Pagan army would later be known to the world for their war elephants as reported by Marco Polo. Pagan Empire By King Anawrahta's accession in 1044, the small principality had gradually grown to include its immediate surrounding area—to about 200 miles north to south and 80 miles from east to west. Over the next 30 years, Anawrahta went on to unify for the first time the regions that would later constitute the modern-day Burma. Anawrahta began his campaigns in the nearer Shan Hills, and extended conquests to Lower Burma down to the Tenasserim coast to Phuket and North Arakan. Anawrahta's conquest of Tenasserim checked the Khmer Empire's encroachment in the Tenasserim coast, and secured control of the peninsula ports, which were transit points between the Indian Ocean and China. After a flurry of military campaigns by Anawrahta, Pagan entered a gilded age that would last for the next two centuries. Aside from a few occasional rebellions, the kingdom was largely peaceful during the period. The most serious was the 1082–1084 rebellion by Pegu (Bago), which nearly toppled the Pagan regime. In the 1110s, Pagan sent two separate