He was born in a Issai vellalar caste to Thiru Muthuvelar and Thirumathi Anjugam Ammaiyar on June 3, 1924 at Thirukkuvalai in the Tanjore District, (now Tiruvarur) Tamil Nadu, India.

Like other well known political figures in this south Indian state, Karunanidhi also has close connections with the Tamil film industry. He started his career as a script writer, first for the stage and later for films.

Some of Karunanidhi’s notable screenplays include Parasakthi (starring Sivaji Ganeshan) and Manthiri Kumari (starring MGR). In all, he is said to have written over 70 screenplays.

Karunanidhi was a close associate of C.N. Annadurai, the founder of the DMK. When Annadurai left the Dravid Kazhagam party over differences with the DK leader Periyar E.V.Ramasamy, Karunanidhi threw in his lot with Annadurai and was named to the propaganda wing.

Karunanidhi was elected to the Tamil Nadu state Legislative Assembly for the first time in the 1957 elections from the Kulithalai constituency. There has been no looking back since for this politician, who is never seen in public without his trademark dark glasses.

When Annadurai became Chief Minister of Tamil Nadu in 1967, he appointed Karunanidhi as public works minister.