According to traditional histories, the Limbu script was first invented in the late 9th century by King Sirijonga Haang, then fell out of use, to be reintroduced in the 18th century by Te-ongsi Sirijunga Xin Thebe.
Accounts with Sirijunga
Limbu, Lepcha and Nepal Bhasa are the only Sino-Tibetan languages of the Central Himalayas to possess their own scripts. (Sprigg 1959: 590), (Sprigg 1959: 591-592 & MS: 1-4) tells us that the Kiranti or Limbu script was devised during the period of Buddhist expansion in Sikkim in the early 18th century when Limbuwan still constituted part of Sikkimese territory. The Kiranti script was probably composed at roughly the same time as the Lepcha script which was by the third King of Sikkim, Phyag-rdor Nam-gyal (ca. 1700-1717). The Kiranti script is ascribed to the Limbu hero, Te-ongsi Sirijunga (translation: Reincarnated Sirijonga; refer to Sirijonga Haang) who was killed by the Tasong monks in conspiracy with the king of Sikkim at the time when Simah Pratap Shah was King of Nepal (i.e. 11 January 1775 to 17 November 1777; Stiller 141,153). Both Kiranti and Lepcha were ostensibly devised with the intent of furthering the spread Buddhism. However, Sirijanga was a Limbu Buddhist who had studied under Sikkimese high Lamas. Sirijanga was given the title 'the Dorje Lama of Yangrup'.
The language and script's influential structure are mixture of Tibetan and Devanagari. Unlike most other Brahmic scripts, it does not have separate independent vowel characters, instead using a vowel carrier letter with the appropriate dependent vowel attached.
|ᤉ||/ɟʱɔ/||Obsolete in modern Limbu.|
|ᤊ||/ɲɔ/||Obsolete in modern Limbu.|
|ᤚ||/ʂɔ/||Obsolete in modern Limbu.|
To change the inherent vowel, a diacritic is added. Shown here on /k/ (ᤁ):
ᤁᤨ represents the same thing as ᤁ. Some writers avoid the diacritic, considering it redundant.
Initial consonant clusters are written with small marks following the main consonant:
Final consonants after short vowels are written with another set of marks, except for some final consonants occurring only in loanwords. They follow the marks for consonant clusters, if any.
Long vowels without a following final consonant are written with a diacritic called kemphreng:
There are two systems for writing long vowels with syllable-final consonants. One system is simply a combination of the kemphreng and final consonant marks:
The other is to write the final consonant with the basic letter, and a diacritic that marks both that the consonant is final, and that the preceding vowel is lengthened:
This same diacritic may be used to mark final consonants in loanwords that do not have final forms in Limbu, regardless of the length of the vowel.
Glottalization is marked by a sign called mukphreng.
Limbu script was added to the Unicode Standard in April, 2003 with the release of version 4.0.
The Unicode block for Limbu is U+1900–U+194F:
Official Unicode Consortium code chart (PDF)