Nirmalananda, born as Tulasi Charan Dutta in Calcutta, was a direct disciple of Ramakrishna,[1] the 19th-century mystic and Hindu saint from India, and took Sanyasa (monastic vows) from Vivekananda along with Brahmananda and others.

Nirmalananda played a key role in establishing Ramakrishna Math and Mission chiefly in South India, in Kerala and Bangalore and Tamil Nadu and also in the USA (in Brooklyn), Burma and Bangladesh (Life of Swami Nirmalananda and old issues of Prabuddha Bharata).

And later he taught the Upanishads, Brahmasutras and Gita to the Brahmacharins at Belur, and he was also able to converse fluently in Sanskrit with the scholars who visited South India.

[2] He first met Ramakrishna in the house of his neighbour Balaram Bose, a lay disciple, in 1882, when Nirmalananda was eighteen years of age.

[3] After the death of their master the a few of the future monastic disciples, led by Narendranath Dutta, later Vivekananda formed the Baranagar Math which Tulasi would visit now and then.

Tulasi joined the Baranagar Math as a permanent resident and became the right hand of Sashi (Swami Ramakrishnananda).

[4] Nirmalananda assisted Ramakrishnananda in serving the brother disciples in both Baranagar and Alambazar Math and was a tireless worker.

He travelled once or twice a year to Kerala and Malabar to establishing ashramas, meet devotees and deliver lectures.

When Vivekananda returned to India from the West in 1897, Nirmalananda was very devoted to the leader and rendered many a service to him, like cooking for him, working as his private secretary and tending to his needs.

At Vivekananda's and other disciples' insistence, Nirmalananda became the assistant secretary of the newly established Ramakrishna Math and Mission.

He stayed in America for two and half years, then returned to India, when Brahmananda called him for 'the regeneration of the Motherland'.

In 1925 he stayed in Trivandrum Ashram for about a month and gave Sanyasa to seven disciples namely Nrisimhananda, Ojasananda, Oorjasananda, Puranjanananda, Balakrishnananda, Arjavananda and Umeshananda.

He started the Kumari Puja and worked for the betterment of women of Namboodiri caste who were socially oppressed.

By a quirk of Providence, this act caused further disquiet in the minds of some minor Trustees of the Ramakrishna Mission, and led to them filing a lawsuit against Swami Nirmalananda in the Bangalore Court.

After five years, in 1935, the court ruled that Ramakrishna Math, Bangalore was indeed a branch of Belur Math, but it also gave the option to Swami Nirmalananda to continue as President of the Bangalore monastery and mandated that a Committee consisting of suitable citizens be formed who would be aiding the President.

He performed many of the household chores in the monasteries and also taught Sanskrit grammar and other scriptures to the new members in the Math.

When the new Math was established in Belur, Tulasi Maharaj worked in gardens and fields together with the new inmates, helped in training them in physical exercises, taught them scriptures and used to play with them.