The Tangsa (also called Tangshang or Hawa) are a cluster of about 70 sub-tribes who live along the border of India and Myanmar. There are just under 100,000 people classed in this people group, approximately ¾ of whom are in Myanmar and ¼ are in India. It is believed that they migrated from the Indo-Tibetan plateau (what is now Mongolia) in the 12th or 13th century. They speak a number of linguistic varieties which are grouped together under the name Tase Naga and given the ISO code "nst". Although these are currently officially classed as one language, in practice many of them function as separate languages, with the level of mutual intelligibility in some cases as low as 35%. There is also a ‘song language’, which seems to be more or less the same across the sub-tribes. The question of whether a single language classification is appropriate for the Tangsa peoples is discussed further by Dr. Stephen Morey in Can a ‘Common Language’ work for the Tangsa?.
The traditional Tangsa belief is that the creator, Lord Rangfraa, gave their ancestors a writing system on deerskin, but they ate it and the script was lost. This is seen as a great loss, and the Tangsa are largely very interested in orthography and literacy development. In recent years, a number of orthographies have been proposed for the Tangsa languages, predominantly based on the Latin script.
In addition, Lakhum Mossang developed a script in 1990, which is genetically unrelated to any existing scripts. This script contains 73 characters, three of which are combining marks, and a set of digits from 0-9. The Mossang variety of the Tangsa language is tonal, and this is reflected in the script by each vowel having four different characters assigned to it, one for each tone. This means that tone is always marked in the writing. It also means that an unusually large proportion of characters in the script (43 of the 73) represent vowels.
(Note that this script is unrelated to the Khimhun script, which is used for writing the same language(s).)
This script is not currently recognized by ISO 15924, but is included in ScriptSource for research purposes. If you have any information on this script, please add the information to the site. Your contributions can be a great help in refining and expanding the ISO 15924 standard.