The first military achievement of Rajaraja’s reign was the campaign inKeralac. 994 CE.Rajaraja created a powerful standing army and a considerable navy which achieved even greater success under his son Rajendra. The prominence given to the army from the conquest of the Pandyas down to the last year of the king’s reign is significant, shows the spirit with which he treated his soldiers. A number of regiments are mentioned in the Tanjore inscriptions and it is evident that Rajaraja gave his army its due share in the glory derived from his extensive conquests.

Due to Rajaraja's desire to record his military achievements in every one of his inscriptions he handed down to posterity some of the important events of his life. As far as we know at present, Rajaraja was the first king of South India to introduce this innovation into his inscriptions. Before his time powerful kings of the Pallava, Pandya and Chola dynasties had reigned in the South, and some of them had made extensive conquests.

The idea of Rajaraja to add a short account of his military achievements at the beginning of every one of his inscriptions was entirely his own. His action in this respect is all the more laudable because his successors evidently followed his example and have left us more or less complete records of their conquests. But for the historical introductions, which are often found at the beginning of the Tamil inscriptions of Chola, kings the lithic records of the Tamil country would be of very little value, and consequently even the little advance that has been made in elucidating the history of Southern India would be difficult.

Raja raja kingdom was control by central governments. Which including king was the sovergin authority the ministers were the advisors and officers. They followed pattelernial inheritance. The chola administration was regulate through royal deccres. the orders of the king were circulated to other officer by the important officer were known as 'olainayakam'. The important feature of raja raja was strong military system including navy