Tondaimandalam, also known as Tondai Nadu, is a historical region located in the northernmost part of Tamil Nadu and southernmost part of Andhra Pradesh. The region comprises the districts which formed a part of the legendary kingdom of Athondai Chakravarti. The boundaries of Tondaimandalam are ambiguous – between the river basins of Penna River and Ponnaiyar River. During the reign of Rajaraja I, this region was called as Jayankonda Cholamandalam.

Nellore district, officially known as Sri Potti Sriramulu Nellore district in Coastal Andhra Region, is one of the 26 districts in the Indian state of Andhra Pradesh. According to the 2011 Census, the district's population was 2,469,712 of which 29.07% was urban. Its administrative headquarters are located in Nellore city. Located in the Coastal Andhra region, the district is bordered by the Bay of Bengal to the east, Kadapa district and Annamayya district to the west, Prakasam district to the north, and Tirupati district to the south.