The earliest examples of a full-length Kannada language stone inscription (shilaashaasana) containing Brahmi characters with characteristics attributed to those of proto-Kannada in Hale Kannada (lit Old Kannada) script can be found in the Halmidi inscription, usually dated c.AD 450, indicating that Kannada had become an administrative language at that time.Ptolemy writes in the midst of the false mouth and the Barios, there is a city called Maganur (Mangalore).He mentions of inland centres of pirates called Oloikhora (Alavakheda).He writes about pirates between Muziris and Nitrias (Netravati River). Nitrias of Pliny and Nitran of Ptolemy refer to the Netravati River as also The Greek geographer Ptolemy (150 CE) mentions places such as Badiamaioi (Badami), Inde (Indi), Kalligeris (Kalkeri), Modogoulla (Mudagal), Petrigala (Pattadakal), Hippokoura (Huvina Hipparagi), Nagarouris (Nagur), Tabaso (Tavasi), Tiripangalida (Gadahinglai), Soubouttou or Sabatha (Savadi), Banaouase (Banavasi), Thogorum (Tagara), Biathana (Paithan), Sirimalaga (Malkhed), Aloe(Ellapur) and Pasage (Palasige) indicating prosperous trade between Egypt, Europe and Karnataka.He also mentions Pounnata (Punnata) and refers to beryls, i.e., the Vaidhurya gems of that country.The scholar Iravatham Mahadevan indicated that Kannada was already a language of rich oral tradition earlier than the 3rd century BCE, and based on the native Kannada words found in Prakrit and Tamil inscriptions of that period, Kannada must have been spoken by a widespread and stable population. The sources of influence on literary Kannada grammar appear to be three-fold: Pāṇini's grammar, non-Paninian schools of Sanskrit grammar, particularly Katantra and Sakatayana schools, and Prakrit grammar.
In the 350 CE Chandravalli Prakrit inscription, words of Kannada origin like punaa Ta, pu Na Da have been used.The palm manuscripts contained texts written not only in Greek, Latin and Hebrew, but also in Sanskrit and Kannada.In the 150 CE Prakrit book Gaathaa Saptashati, written by Haala Raja, Kannada words like t Ir or Teer (meaning to be able), tuppa, pe TTu, po TTu, po TTa, pi TTu (meaning to strike), Pode (Hode) have been used.The Halmidi inscription provides invaluable information about the history and culture of Karnataka.Recent reports indicate that the Old Kannada Nishadi inscription discovered on the Chandragiri hill, Shravanabelagola, is older than Halmidi inscription by about fifty to hundred years and may belong to the period AD 350–400. Shettar is of the opinion that an inscription of the Western Ganga King Kongunivarma Madhava (c.