Kottarathil Sankuni, born 4th April 1855, was second son of Vasudevan Unni of Kottarathil family, Kodimatha, Kotttayam, South Kerala. Baby boy was named Vasudevan. Father and son had same name. Mother called him Thanku. Thanku eventually became Sanku. Sanku, till age of ten, was educated by different gurus.

He, at the age of 17, studied Sidtha Roopam (Sanskrit grammar) from Sanku Warior, Manarcadu.

Vayaskara Aryan Narayanan Moosu taught him chapters of Raghu Vamsam, Magham, Naishadham (Sanskrit literature) and Sahasra Yogam,Guna Padham, Chikitsa Kramam, Ashtanga Hridayam ( Sanskrit books of ayurvedic cure ). He took responsibility of family in 1881. But self learning continued. He, at the age of 36, wrote Subhadra Haranam Mani Pravalam and Kesava Dasa Charitram.
He taught Malayalam language to several Europeans since 1883 to 1885.
He was introduced to Kandathil Varughese Mappiali of Malayala Manorama by Vayaskara Moosu in 1888.

He joined editorial board of Malayala Manorama in 1890. He wrote, periodically, Ithyhiya Mala (Lore and legacy of Kerala) for Bhasha Poshini.
He was appointed first Malayalam language teacher of Mar Dioniosius Seminary high school, Kottayam in 1893.

He received several literary awards from states of Thiruvithamcore, Kochy and British Malabar. He was titled ‘Kavi Thilakan’ by Maha Raja of Kochi in 1919.
He left this world in 1937.