The Tangut people were a Sino-Tibetan people who founded and inhabited the Western Xia dynasty. The group initially lived under Tuyuhun authority, but later submitted to the Tang dynasty. After the collapse of Tang dynasty, the Tanguts established the Western Xia. They spoke the Tangut language, which initial research believed to be either of the Qiangic or Yi groups of the Tibeto-Burman family, later phylogenetic and historical linguistic accounts revealed that it belonged to the Gyalrongic branch of the Qiangic group. The Western Xia was annihilated by the Mongol Empire in 1227 AD, and most of its written records and architecture were destroyed. Today the Tangut language and its unique script are extinct; only fragments of Tangut literature remain.