Sthanu Ravi Varman

Sthanu Ravi Varman (Tamil:தாணு ரவி வர்மா Malayalam: സ്ഥാണു രവി വർമ) was the ruler of the Later Chera Kingdom from 844 to 885 (from 844 to 883 according to MGS). His reign was noted for developments in science, economic prosperity and political stability. He was succeeded by Rama Varma Kulasekhara.
The Chera-Chola relations were friendly during his rule. No Chola invasion of any part of the Chera Kingdom is known to have taken place during this period. He was the contemporary of the famous Chola emperor, Aditya Chola. It is known that the two rulers jointly conferred a title on a chief of Tanjore called Vikki Annan. He also helped the Chola king with his army to fight against the Pallavas.

The famous astronomer Sankara Narayana (the author of Sankara Narayaniyam, a commentary of Bhaskara's Laghu Bhaskariya) was member of the royal palace of Sthanu Ravi at Mahodayapuram. It was on the basis of Sankara Narayaniyam, the date accession of Sthanu Ravi was fixed at 844 AD. Ayyan Atikal Tiruvatikal, the Governor of Venadu (Quilon) under Sthanu Ravi, issued the famous the Terisappalli Copper Plate (849 AD). The inscription describes the gift of land to the Teresa Church near Quilon along with several rights and privileges to Christians led by Mar Sapir Iso.
Koyiladhikarikal (Royal Temple Manager, usually held by the king's elder son and the Heir Apparent) during the time of Sthanu Ravi was his son-in-law Vijaya Raga Deva.
The Arab merchant Sulaiman visited the Chera Kingdom in 851. He mentions the brisk trade between China and Cheras in this period.
The Tillaisthanam inscription testifies to the cordial relations between Aditya Chola and Sthanu Ravi.
There is an inscription of Sthanu Ravi in the Kudalmanikyam temple at Irinjalakkuda dated to 855.