invasion by Nanzhao that shattered the Pyu city-states. Other Burmish languages are still spoken in Dehong Prefecture in the far west of Yunnan. By the 11th century, their Pagan Kingdom had expanded over the whole basin. The oldest texts, such as the Myazedi inscription, date from the early 12th century. The closely related Loloish languages are spoken by 9 million people in the mountains of western Sichuan, Yunnan and nearby areas in northern Myanmar, Thailand, Laos and Vietnam. The Tibetic languages are spoken by some 6 million people on the Tibetan Plateau and neighbouring areas in the Himalayas and western Sichuan. They are descended from Old Tibetan, which was originally spoken in the Yarlung Valley before it was spread by the expansion of the Tibetan Empire in the seventh century. Although the empire collapsed in the ninth century, Classical Tibetan remained influential as the liturgical language of Tibetan Buddhism. The remaining languages are spoken in upland areas. Southernmost are the Karen languages, spoken by 4 million people in the hill country along the Myanmar–Thailand border, with the greatest diversity in the Karen Hills, which are believed to be the homeland of the group. The highlands stretching from northeast India to northern Myanmar contain over 100 high-diverse Sino-Tibetan languages. Other Sino-Tibetan languages are found along the southern slopes of the Himalayas and the eastern edge of the Tibetan plateau. The 22 official languages listed in the Eighth Schedule to the Constitution of India include only two Sino-Tibetan languages, namely Meitei (officially called Manipuri) and Bodo. Homeland There have been a range of proposals for the Sino-Tibetan urheimat, reflecting the uncertainty about the classification of the family and its time depth. Three major hypotheses for the place and time of Sino-Tibetan unity have been presented: The most commonly cited hypothesis associates the family with the Neolithic Yangshao culture (7000–5000 years BP) of the Yellow River basin, with an expansion driven by millet agriculture. This scenario is associated with a proposed primary split between Sinitic in the east and the Tibeto-Burman languages, often assigned to the Majiayao culture (5300–4000 years BP) in the upper reaches of the Yellow River on the northeast edge of the Tibetan plateau. For example, James Matisoff proposes a split around 6000 years BP, with Chinese-speakers settling along the Yellow River and other groups migrating south down the Yangtze, Mekong, Salween and Brahmaputra rivers. George van Driem proposes a