 The Emperor of the Song Dynasty consented and sent envoys in return to be formally entitled Lý Thái Tổ as the "emperor of Đại Việt" superseding the title "Lord of Giao Chỉ", In turn, some vassal kingdoms of Đại Việt to the south such as Champa (modern-day central Vietnam) and Chenla (modern-day Cambodia) brought annual tributes to Đại Việt, allowing Lý Thái Tổ to ensure good relations between these neighboring kingdoms.Lý Thái Tổ's political skills enabled Đại Việt to secure peace with its neighboring kingdoms to the north and south.During his reign, Đại Việt had a stabilized political infrastructure and good relations with its neighbors, which enabled Đại Việt's economic development to flourish.