In 1036 CE, the emperor Li Yuanhao of the Western Xia (Xixia / 西夏) dynasty decreed a writing system for the Tangut language. His scholar Yeli Renrong is said to have invented the script in a matter of years: roughly 6,000 logographs, each a new design that resembles Chinese characters without borrowing from them. The result is Tangut (西夏文), a script with dense, square, multi-part characters.
The Western Xia empire, centred on what is now Ningxia and Gansu in north-west China, lasted nearly two centuries — long enough to produce Buddhist canons, dictionaries, law codes, dynastic histories, and a vast bureaucracy, all in Tangut. Then in 1227 the Mongols under Genghis Khan razed it. Tangut outlived its empire by centuries. Communities scattered east kept writing it as a liturgical and scholarly language, and the last datable Tangut texts are two Buddhist dhāraṇī pillars raised at Baoding in Hebei — some 800 km east of the old Xixia capital — in 1502, the middle of the Ming. After that the script vanished from active use.
What linguists eventually rediscovered was a Sino-Tibetan language — most likely on the Qiangic branch — with a two-way tone contrast (level 平聲 vs. rising 上聲), complex initial consonant clusters reconstructed from rhyme tables, and a fondness for compound logographs in which radicals are borrowed from one another rather than from any Chinese ancestor. A typical Tangut character has 15–20 strokes; some have over 30.
- Created, not evolved. Unlike Chinese, whose characters grew organically over millennia, every Tangut logograph was designed at once, in a single imperial workshop. This is one of the very few large-scale "constructed" scripts in human history.
- Phonology by table. Because no native speaker survives, all Tangut sound reconstruction depends on bilingual rhyme dictionaries — especially the Wénhǎi (文海) and Tóngyīn (同音), which group characters by initial, rhyme and tone.
- A Buddhist library underground. In 1908 the Russian explorer Pyotr Kozlov reached the ruined city of Khara-Khoto and began digging; on his return in June 1909 he opened a stupa outside its walls and shipped thousands of Tangut books and manuscripts to St Petersburg — still the world's largest collection.
The scholar who did most to crack it was Nikolai Nevsky (1892–1937), a Russian Japanologist who spent the 1920s in Japan and Taiwan. He took up the Khara-Khoto hoard in 1925, while still living in Japan, and after returning to Leningrad in 1929 he spent the following decade working out its phonological structure and building the first Tangut–Russian dictionary. His masterpiece, Tangutskaya Filologiya, was published posthumously in 1960 — Nevsky himself had been shot in Stalin's Great Purge in 1937. He was awarded the Lenin Prize after death.
Tangut characters occupy square blocks built from recurring graphic components. Their structure is logographic rather than an alphabetic sequence of strokes.
Later Mikhail Sofronov refined the phonological reconstruction in the 1960s; Ksenia Kepping worked on grammar and ritual texts; today researchers in Beijing, Kyoto, Taipei and St Petersburg continue to publish editions of newly catalogued manuscripts. Significant questions remain — the exact tone system, the deeper genetic position within Sino-Tibetan, the meaning of dozens of rare characters that occur only once or twice in the corpus.
Tangut was created within a decade, used for centuries, and then fell out of active use for roughly four centuries. Modern reconstruction relies on surviving manuscripts, bilingual dictionaries, and rhyme tables.