As a colleague of Mahatma Gandhi, Motilal Nehru and Dr. Rajendra Prasad, among others, Nilakantha played a key role in the Indian Independence movement.

He was a prime architect in creating the independent Odisha Province in 1936, who worked untiringly as the right-hand man of Madhusudan Das to achieve this goal.

His grandfather was a well-to-do landowner and the chief of his village, but died young at the age of 28.The family then lost all their property due to British Government imposed ‘Sunset laws’ for tax collection from the people of Odisha.

During his high school days, Nilakantha came under the strong influence of Pandit Gopabandhu Das, whom he always respected deeply and regarded as his mentor.

Along with Acharya Harihara and another friend, he took a vow with Gopabandhu on the banks of river Bhargavi near Puri, not to accept any jobs under the British Government, and to dedicate their lives for the service of their motherland.

Moreover, Nilakantha led grass-root efforts to bring other bicchinna or annexed Odia speaking regions in Bihar with frequent trips to those areas as well.

Nilakantha was greatly inspired by Madhusudan Das's goal for the amalgamation (unification) of all Odia speaking regions under one administration by first attending his Utkala Sammilani in 1903 and then meeting directly with him in 1904.

In 1917, Nilakantha presided over the Manjusha session of Utkala Sammilani and greatly helped in strengthening the demand for amalgamation of scattered Odia-speaking tracts including undivided Koraput, Ganjam, Paralakhemundi etc.

So Madhusudan and other prominent leaders of this movement (such as: Maharaja Shri Krushna Chandra Gajapati of Paralakhemundi), were willing to just put the cash-stripped amalgamated Odia-speaking regions as a sub-province under a single governing state, preferably Madhya Pradesh.

After being elected to the Delhi Central Assembly in 1924, he became instrumental in creating the current independent Odisha Province, not just an amalgamated region or sub-province, in the important ways described below.

Then Nilakantha bypassed many other hurdles in the Central Assembly and finally moved a resolution there in 1927, which asked for All Oriya-speaking tracts to be put under one local administration, in the form an independent, linguistically-based Orissa Province, claiming that "otherwise Odias won’t be satisfied and agitations would continue.” He also reintroduced the resolution in All India Congress session in 1929 in spite of opposition at central level, and rejected an offer of Sir title  by Mr. Alexander Muddiman, Finance Secretary, Government of British India, to accept Odisha as a sub-province.

Nilakantha Das was responsible for the inclusion of southern regions, including Koraput, Paralakhemundi and Ganjam up to Chilika, in Odisha when it was formed on April 1, 1936.

But Nilakantha presented historical facts and concrete evidence to the contrary, based on his in-depth research on the cultural heritage of the Southern Odisha regions, which the Andhra committee could not refute and was forced to relinquish its claim once for all.

He successfully argued that the poverty and underdeveloped nature of the annexed areas should be an important reason for bringing them to Odisha and improving their condition concurrently with the rest of the state.

Madhusudan Das, who died in February, 1934, was not alive to see the formation of this new, independent Odisha Province, but prior to his death he expressed his full confidence in Nilakantha in carrying on his legacy and bringing his dreams to fruition.

[10] Nilakantha was later proclaimed as the “Veritable father of Orissa” by Prof. N. G. Ranga, Deputy Leader of the Congress Party in the Indian Parliament (1980–1991), because of his extraordinary, pioneering efforts in this regard.

The fourth volume in the series, titled Eminent_Parliamentarians_Series_Nilakantha_Das,[15] contains his speeches delivered in the Central Legislative Assembly, while participating in debates on local, national and international issues.

Taking part in many activities related to the Indian Independence movement, Nilakantha was jailed four times by the British Government, spending a total of more than two and half years there.

[6] Nilakantha's in-depth research, presentation of facts and inspiring speeches had endeared him to many leaders in the Indian political arena, Dr. Rajendra Prasad, Govind Ballav Pant, Acharya Kriplani and Motilal Nehru, to name a few.

Nilakantha wrote many other books, both for adults and for children, including two Kavyas as adapted versions of Tennyson, namely Dasa Nayak (Enoch Arden) and Pranayini (The Princess).

[5] He was against many social and cultural restrictions imposed by upper class Brahmins and wrote a series of articles, under the title Mo Nisha (My Mustache) in the well-known monthly magazine of the time called "Mukura" to protest against it.

Nilakantha was influenced by the doctrines of Jain Dharma, and found great parallelism between Jainism and Jagannath culture, both focusing on the equality of all men rather than on a supreme God.

Pandit Nilakantha was a simple and righteous man, prone to sudden flair of temper upon witnessing wrong things, but equally apt to cool down immediately if realized his own mistakes.

In the true sense, he was forever a strict school master, who did not tolerate any weakness in his students, but appreciated and encouraged all their good qualities and helped them whole-heartedly to achieve their best.

When Nilakantha wanted to join the Indian Independence movement, on the advice of Gopabandhu Das, he requested his father-in-law to take care of his young family and elderly parents.

For most part of his active life, Nilakantha did not even possess a car, and on returning from Delhi, Cuttack or other places, used to travel the two miles from the Sakhigopal Railway station to his village home in bullock carts.

He was given the Padma Bhusan award for Public Affairs in 1957, which was delivered to him personally by the then President of India, Dr. Rajendra Prasad at his Government residence in Bhubaneswar since he was unable to travel to Delhi.

For his 75th birthday, many eminent persons, including Pandit Jawaharlal Nehru, Gobinda Ballav Pant, Dr. Rajendra Prasad, Mr. Bhimsen Sachar sent him their admiring messages.

To preserve his valuable works and to acknowledge his astounding contributions in a wide range of fields, a Trust called Nilakantha Smruti Samiti was founded in 1978, with Dr. Sadashiva Misra (renowned economist and Ex-Vice Chancellor of Utkala University) as its president.

The non-profit Samiti holds a vast repository of Nilakantha's published writings in prints and book form, as well as articles of many prominent people on his many different accomplishments.