Pillai was born on 26 December 1879 as the only son of Padmanabha Pillai, a Government School Inspector, who hailed from the then South Travancore. A. R. Pillai's mother, Narayani Pillai Kaaliyamma Pillai, niece (maternal cousin's daughter) of the famous Easwara Pillai Vicharippukar, was a member of an aristocratic and affluent Hindu (Nair) matriarchal/matrilineal joint family. The family lived in a large complex of buildings known as Punnackal, situated on the western side of Sri Padmanabhaswamy temple inside the Fort, Thiruvananthapuram. The house had been built for Easwara Pillai Vicharippukaar, the celebrated doyen of Kathakali actors of Valia Kottaaram Kathakali Yogam of 19th century Travancore State and Palace manager (Palliyara Vicharippukaar) in the Travancore Palace, by his patron and king, Uthram Thirunaal MarthandaVarma.