Hồ dynasty
Vietnamese scholars were thus intimately familiar with Chinese writing. In order to record their native language, they applied the structural principles of Chinese characters to develop "chữ Nôm". The new script was mostly used to record folk songs and for other popular literature. Vietnamese written in "chữ Nôm" briefly replaced Chinese for official purposes under the Hồ dynasty (1400–1407) and under the Tây Sơn (1778–1802), but in both cases this was swiftly reversed.