Nam quốc sơn hà

Nam quốc sơn hà (, lit. 'Mountains and Rivers of the Southern Country') is a famous 10th- to 11th-century Vietnamese patriotic poem. Dubbed "Vietnam's first Declaration of Independence", it asserts the sovereignty of Vietnam's rulers over its lands. The poem was first dictated to be read aloud before and during battles to boost army morale and nationalism when Vietnam under Lý Thánh Tông and Lý Thường Kiệt fought against two invasions by Song dynasty in 981 and 1075–1076 and would become became an emblematic hymn in the early independence wars. The poem is one of the best-known pieces of Vietnamese literature.

The poem's exact authorship, origin, and style of writing are still controversial. According to K.W. Taylor, the account of the poem comes from the 14th-century Buddhist scripture Thiền uyển tập anh and if the story of the poem is true, then the poem could not have been sung in the form it currently exists today. The poem is written in Classical Chinese in the form of an oracle following Tang-style rules that would have been hard to understand for Viet soldiers. It would also be the only literary work known to have been written by Lý Thường Kiệt, who was not a literary man. The story of singing in temples to boost military morale prior to battle is plausible, but whether or not it was this specific poem that was sung cannot be answered. It is possible that it was written after the event.

981 version
Lĩnh Nam chích quái ("Selection of Strange Tales from Lingnan") dates this version to the Song–Đại Cồ Việt war:

1076 version
Đại Việt sử ký toàn thư ("Complete Historical Annals of Great Viet") dates this version to the Song–Đại Việt war: