K C Mammen Mappillai was born on 4th of May 1873 as the eldest son of Kandathil Cherian Mappillai and Mariamma. He had 2 older sisters 5 younger brothers and 2 younger sisters.

He passed Matriculation from Thiruvalla High School, Intermediate (F A) from C M S College, Kottayam and B A from Madras Christian College.

After passing B A., he wanted to enter the Mysore Civil Service like some of his college-mates. But his uncle Varghese Mappillai, founder of Malayala Manorama persuaded him to come back to Kerala and become a school teacher.
He joined M D Seminary High School and become its Headmaster. Varghese Mappillai persuaded his nephew to help him in the working of Malayala Manorama.
Varghese Mappillai passed away in July 1904, And the mantle of publishing the newspaper fell on the shoulders of Mammen Mappillai who was just 31 years old.

He resigned his Headmastership in 1908 and took over the publishing of Manorama as full time job. He became its longest Editor. During his time Manorama became a bi-weekly in 1918 and Daily in 1928.

Along with publishing he went into a number of business projects some of which never saw the light of Day. Shipping, Road Transport, Retail Shop, Book Publications etc. were some of them. However, he gave Kerala's economy a new bounce. He used Malayala Manorama to popularise cultivation, particularly rubber, the MONEY TREE from Brazil. Rubber eventually became backbone of Kerala midlands and continues to be so.

One of the other institutions he had started was Travancore National bank. It was later amalgamated with Quilon Bank started by C P Mathen in 1936. The new name was Travancore National & Quilon Bank.

He took active part in the struggle of the Malankara Church against the Antiochian hegemony.

He was a member of the Modern Legislative Assembly of the Erstwhile State of Travancore. He played a key role in the struggle for Civil Rights and responsible Government.

The various activities of K C Mammen Mappillai were not appreciated by the then Dewan of Travancore Sir C P Ramaswamy Iyer, particularly his political activities, which had the support of his newspaper.

The Dewan of Travancore went all out to break the political activities of K C Mammen Mappillai. He made the Travancore Government seal the newspaper office. Owing to the adverse propaganda by Government the bank closed in 1938.

K C Mammen Mappillai was arrested and put in jail for 2 years.

In 1947 after India became independent he came back to Kerala and restarted Malayala Manorama on 29th November 1947. He ran it with his eldest son K M Cherian till his death at midnight on December 3, 1953.

His anchor all through the crests and troughs was Mammy, his wife whom he married when he was just fifteen. She inspired him, comforted him and bore him nine children, all of whom made a mark in their chosen fields.

As a mark of respect to his departed soul, the Chief Minister of the then Travancore- Cochin, Sri A J John and his cabinet ministers led the funeral procession, which was a signal honour considering what the previous Dewan-led Government did to Malayala Manorama an K C Mammen Mappillai.

His legacy lives on-in Malayala Manorama's undying love for freedom and in his indelible imprint on Kerala's destiny.