• Karikala was an important Chola ruler of the Sangam period, who was famous for his military achievements. Vijayalaya, on the other hand, was the founder of the Imperial Chola Dynasty that began in the medieval period (9th century). He is accredited with re-establishing the Chola rule and had his capital in Thanjavur.

• Pattinappalai portrays Karikala’s early life and his military conquests. In the Battle of Venni, he defeated the mighty confederacy consisting of the Cheras, Pandyas and eleven minor chieftains. This event is mentioned in many Sangam poems. Vahaipparandalai was another important battle fought by him, in which nine enemy chieftains submitted before him. Karikala’s military achievements made him the overlord of the whole Tamil country.

• Hereditary monarchy was the form of government during the Sangam period. The king took advice of his minister, court-poet and the imperial court or avai. The Chera kings assumed titles like Vanavaramban, Vanavan, Kuttuvan, Irumporai and Villavar; the Chola kings like Senni, Valavan and Killi; and the Pandya kings Thennavar and Minavar.