Mohan Kumaramangalam was born in London to P. Subbarayan, then zamindar of Kumaramangalam in Salem district and later, Chief Minister of Madras Presidency and his wife, Radhabai Subbarayan on 1 November 1916.
Mohan Kumaramangalam lahir di London dari P. Subbarayan, kemudian zamindar Kumaramangalam di distrik Salem dan kemudian, Ketua Menteri Kepresidenan Madras dan istrinya, Radhabai Subbarayan pada 1 November 1916.