This section is from the book "Some Contributions Of South India To Indian Culture", by S. Krishnaswami Aiyangar. Also available from Amazon: Some Contributions of South India to Indian Culture.
In the meanwhile changes of a momentous character had taken place to the west of the Pallava territory. The region of the Naga chieftains, cousins of the ruling Satavahanas, had been taken either in the reign of Skandavar-man himself or his somewhat feeble successor by an enterprising Brahman who succeeded almost as a rebel in putting an end to the Pallava power in the northern half of their territory extending southwards from Sri Sailam. He extended his power so far as to levy contributions from the territory of the Banas immediately to the west and south of the Pallava territory proper. The Pallavas apparently recognised his hold upon his native country by conferring it as a fief upon him thereby purchasing peace and perhaps a restoration of the Pallava territory of the Ceded Districts. This achievement of Mayura Sarman, the Veda Scholar, must have taken place in the reign of Skandavarman himself or in that of his son Simhavarman. A certain number of generations of these had actually ruled. We find the Pallavas slowly gaining strength and reasserting their authority over the Gangas by successively annointing and thus ratifying the succession of two Ganga rulers. The inference of a weakening of the power of the Kadambas at that time seems possible and this was taken advantage of by a feudatory dynasty of the Kadambas, themselves a dynasty connected with them by blood and perhaps similarly claiming authority from the Satavahanas themselves. These are the western Chalukyas who like the Kadambas claimed to belong to the Manavyasa Gotra, and described themselves as Harltiputra. Their, later charters trace their descent from the rulers of Ayodhya and lay claim, in their behalf, to belong to the family of Ikshvakus; the Cholas laid claim to the same descent as did Sri Vira Purusha Datta, the interloper in the eastern half of the 26
Andhra territory. By the time that Simhavishnu had placed himself firmly on the throne of Kanchi, the Chalukyas had so far established themselves in power first in the north-western part of the Andhra dominions gradually extending downwards to occupy what belonged to the Cutu Nagas, the cousin-viceroys of the Andhras. It is in this frontier that they came into contact with the Pallavas necessarily hostile as it meant an expansion of Chalukya power and territory in that direction. It is then there began the war between the Chalukyas and the Pallavas which is the feature of their later history.