The Chola dynasty was one of the longest-ruling dynasties in the history of India. Till 850 A.D Cholas were paying tributes to Pallavas. But they retain enough prestige that their daughters often got married to Pallava and Pandya families. As Cholas were also equally powerful to them till 350 A.D after that their power declined. In 850 A.D war broke between  Pallava and Pandya kingdom and at this time then Chola king Vijayalaya renounced his Pallava over-lord and captured the city of Thanjavur and announced it as their new capital. This marked the start of medieval Cholas and also the peak of Chola empires.

Son of Vijayalaya, Aditya 1 went on defeating the Pandya kingdom and Pallava kingdom in 885 A.D and 897 A.D respectively. The Cholas ruled all over the Tamil region. After defeating the Pallava kingdom and Pandya kingdom there was no other regional power which could oppose them. Cholas started their conquest to Srilanka in 925 A.D. The next two great rulers of the Chola empire were Rajaraja Chola (r. 985-1014 A.D)  and Rajendra Chola(r. 1012-1044 A.D) they expanded the empire still further.
Rajaraja Chola pushed the northern boundaries out of Tamil region to Kalinga in the northeast of India and sent his navy to capture the island nation  Maldives and also the rich Malabar coast along the subcontinent's southwestern shore. These territories were important, as they were the trade routes, and so they had captured it. So that there would be no trouble along Indian ocean trade routes. Rajendra Chola further expanded beyond the mighty river Ganga. Regions like Bihar, Bengal come under his control and he also had taken the coastal line of  Burma (Myanmar), the Andaman and Nicobar Islands, and the key ports in the Indonesian archipelago and the Malay Peninsula. So we can say that it was the first true maritime empire based in India. The Chola Empire under Rajendra even exacted tribute from Siam (Thailand) and Cambodia. 

Cultural and artistic influences flowed in both directions between Indochina and the Indian mainland. Although Cholas had a powerful army and navy power, the  Chalukya empire in the western Deccan plateau, rose up periodically and tried to throw off The Chola dominance. After decades of intermittent warfare, the Chalukya kingdom collapsed in 1190 A.D. The Chola Empire, however, did not long outlast its gadfly.  It was an ancient rival that finally did in the Cholas for good. Between 1150 and 1279, the Pandya family gathered its armies and launched a number of bids for independence in their traditional lands. The Cholas under Rajendra III fell to the Pandyan Empire in 1279 A.D and ceased to exist.

The Chola Empire left a rich legacy in the Tamil country. It saw majestic architectural accomplishments such as the Thanjavur Temple, amazing artwork including particularly graceful bronze sculpture, and a golden age of Tamil literature and poetry. All of these cultural properties also found their way into the Southeast Asian artistic lexicon, influencing religious art and literature from Cambodia to Java. Thus Chola time is also called a "GOLDEN PERIOD OF SOUTH INDIA"