[3][4] Jatin was born in a Bengali Brahmin family[5] to Sharatshashi and Umeshchandra Mukherjee in Kayagram, a village in Kushtia, the then part of undivided Nadia district, in what is now Khulna Division, Bangladesh, on 7 December 1879.

Since the age of 14, Tagore had claimed in meetings organised by his family members equal rights for Indian citizens inside railway carriages and in public places.

Soon he started visiting Swami Vivekananda, whose social thought, and especially his vision of a politically independent India – indispensable for the spiritual progress of humanity – had a great influence on Jatin.

The Swami taught him the art of conquering libido before raising a batch of young volunteers "with iron muscles and nerves of steel", to serve miserable compatriots during famines, epidemics and floods and running clubs for "man-making" in the context of a nation under foreign domination.

Fed up with the colonial system of education, Jatin left for Muzaffarpore in 1899, as secretary of barrister Pringle Kennedy, founder[citation needed] and editor of the Trihoot Courrier.

In 1903, on meeting Sri Aurobindo at Yogendra Vidyabhushan's place, Jatin decides to collaborate with him and is said to have added to his programme the clause of winning over the Indian soldiers of the British regiments in favour of an insurrection.

W. Sealy in his report on "Connections with Bihar and Orissa" notes that Jatin Mukherjee "a close confederate of Nani Gopal Sen Gupta of the Howrah Gang (...) worked directly under the orders of Aurobindo Ghosh.

"[13] In 1905, during a procession to celebrate the visit of the Prince of Wales at Calcutta, Jatin decides to draw the attention of the future Emperor on the behaviour of HM's English officers.

Not far from the royal coach, he singles out a cabriolet on a side-lane, with a group of English military men sitting on its roof, their booted legs dangling against the windows, seriously disturbing the livid faces of a few native ladies.

Whereas Jatin disapproved of all untimely terrorist action, Barin led an organisation centred around his own personality: his aim was, aside from the general production of terror, the elimination of certain Indian and British officers serving the Crown.

Organising relentless relief missions with a paramedical body of volunteers following almost a military discipline, during natural calamities such as floods or epidemics, and religious pilgrimages such as the Ardhodaya Yog in Calcutta and the Kumbha Mela, or the annual celebration of Ramakrishna's birth, Jatin was suspected of utilising these as pretexts for group discussions with regional leaders and recruiting new freedom fighters to fight the supporters of the British.

"[18] In April 1908, in Siliguri railway station, Jatin got involved in a fight with a group of English military officers headed by Captain Murphy and Lt Somerville, leading to legal proceedings, widely covered by the press.

[citation needed] Warned by the Magistrate to behave properly in the future, Jatin regretted that he would not refrain from taking similar action in self-defence or in the vindication of the rights of his countrymen.

Hence, during the Alipore trial, Jatin took over the leadership of the secret society to be known as the Jugantar Party, and revitalised the links between the central organisation in Calcutta and its several branches spread all over Bengal, Bihar, Odisha and several places in Uttar Pradesh.

[citation needed] Through Justice Sarada Charan Mitra, Jatin leased from Sir Daniel Hamilton lands in the Sundarbansto shelter revolutionaries not yet arrested.

Atul Krishna Ghosh and Jatindranath Mukherjee founded Pathuriaghatat Byam Samity which was an important centre of armed revolution of the Indian national movement.

After the Alipore Case, Jatin organized a series of what author Arun Chandra Guha describes as "daring" actions in Calcutta and in the districts, "to revive the confidence of the people in the movement ...

[24] Almost contemporaneous with the anarchist Bonnot Gang well known in France, Jatin invented and introduced in India bank robbery on automobile taxi-cabs, " a new feature in revolutionary crime.

On 25 January 1910, "with the gloom of his assassination hanging over everyone", the Viceroy Minto declared openly: "A spirit hitherto unknown to India has come into existence (...), a spirit of anarchy and lawlessness which seeks to subvert not only British rule but the Governments of Indian chiefs..."[26][27] On 27 January 1910, Jatin was arrested in connection with this murder, but was released, to be immediately re-arrested along with forty-six others in connection with the Howrah-Sibpur conspiracy case, popularly known as the Howrah Gang Case.

[25] While held in Howrah jail, awaiting trial, Jatin made contact with a few fellow prisoners, prominent revolutionaries belonging to various groups operating in different parts of Bengal, who were all accused in this case.

Jatin went on to Brindavan where he met Swami Niralamba (who had been Jatindra Nath Banerjee, the renowned revolutionary, before leading a sanyasi's life); he had continued preaching in North India Sri Aurobindo's doctrine of a revolution.

Impressed by Jatin's "fiery energy and personality", Bose sounded out non-commissioned officers posted at the Fort William of Calcutta, the nerve centre of the various regiments of the colonial army, before returning to Benares "to organise the scattered forces.

The Bengali bestseller Dhan Gopal Mukerji, settled in New York and, at the summit of his glory, was to write : "Before 1914 we succeeded in disturbing the equilibrium of the government... Then extraordinary powers were given to the police, who called us anarchists to prejudice us forever in the eyes of the world... Dost thou remember Jyotin, our cousin – he that once killed a leopard with a dagger, putting his left elbow in the leopard's mouth and with his right hand thrusting the knife through the brute's eye deep into its brain?

"[37] Right since 1907, Jatin's emissary, Taraknath Das had been organising, with Guran Ditt Kumar and Surendramohan Bose, evening schools for Indian immigrants (a majority of them Hindus and Sikhs) between Vancouver and San Francisco, through Seattle and Portland: in addition to learning how to read and write simple English, they were informed about their rights in the USA and their duty towards Mother India: two periodicals – Free Hindustan (In English, sponsored by local Irish revolutionaries) and Swadesh Sevak ('Servants of the Motherland', in Gurumukhi) – became increasingly popular.

Familiar with the doctrine of Sri Aurobindo and an erstwhile follower of Rasbehari Bose, in 1913, invited by Das, Har Dayal resigned from his teaching job at the University of Berkeley, coaxed by Jiten Lahiri (one of Jatin's emissaries) of wasting his time in daydreaming, Har Dayal set out on a lecture tour covering the major centres of Indian immigrants; enlivened by their patriotism, he preached open revolt against the English rulers of India.

Advised by Berlin, Ambassador Bernstorff in Washington arranged with Von Papen, his military attaché, to send cargo consignments from California to the coast of the Bay of Bengal, via Far East.

To facilitate transmission of information to Jatin, a business house under the name "Universal Emporium" was set up, as a branch of Harry & Sons in Calcutta, which had been created for keeping contacts with revolutionaries abroad.

In April 1915, after meeting with Jatin, Naren Bhattacharya (the future M. N. Roy) went to Batavia, to make a deal with the German authorities concerning financial aid and the supply of arms.

With occasional skirmishes, the revolutionaries, running through jungles and marshy land in torrential rain, finally took up position on 9 September 1915 in an improvised trench in the undergrowth on a hillock at Chashakhand in Balasore.

Professor Tripathi analysed the added dimensions revealed by the Howrah Case proceedings: acquire arms locally and abroad; raise a guerrilla; create a rising with Indian soldiers; Jatin Mukherjee's action helped improve (especially economically) the people's status.