The Limbu or Kirati alphabet was probably modelled on the
Lepcha alphabet, which is thought to
have derived from the Tibetan
alphabet. According to many historians, King Sirijonga invented
the "Kirat-Sirijonga Script" in the late 9th century. It disappeared
for many years and was then reintroduced by Te-ongsi Sirijonga
(believed to be reincarnation of King Sirijonga), in the 17th century.
In 1925, Iman Singh Chemjong, a Limbu scholar, named the script
after Sirijonga who had laid down his life for the preservation
and promotion of script in 1743.