History of India's Chola Empire
Nobody knows exactly when the first Chola kings took power in the southern point of India, but certainly, the Chola Dynasty was established by the third century BCE, because they are mentioned in one of Ashoka the Great's stelae. Not only did the Cholas outlast Ashoka's Mauryan Empire, they continued to rule until 1279 CE—more than 1,500 years.
The Chola Empire was based in the Kaveri River Valley, which runs southeast through Karnataka, Tamil Nadu, and the southern Deccan Plateau to the Bay of Bengal. At its height, the Chola Empire controlled not only southern India and Sri Lanka, but also the Maldives. It took key maritime trading posts from the Srivijaya Empire in what is now Indonesia, enabling a rich cultural transfusion in both directions, and sent diplomatic and trading missions to China's Song Dynasty (960 - 1279 CE).
The origins of the Chola Dynasty are lost to history. The kingdom is mentioned, however, in early Tamil literature, and on one of the Pillars of Ashoka (273 - 232 BCE). It also appears in the Greco-Roman Periplus of the Erythraean Sea (c. 40 - 60 CE), and in Ptolemy's Geography (c. 150 CE). The ruling family came from the Tamil ethnic group.
Around the year 300 CE, the Pallava and Pandya Kingdoms spread their influence over most of the Tamil heartlands of southern India, and the Cholas went into a decline. They likely served as sub-rulers under the new powers, yet they retained enough prestige that their daughters often married in to the Pallava and Pandya families.