[6] The Mitra family traced its origins to ancient Bengal;[4] and Rajendralal further claimed descent from the sage Vishvamitra of Adisura myth.

[3][9] Janmajeya was a noted oriental scholar, who was revered in Brahmo circles and was probably the first Bengali to learn chemistry; he had also prepared a detailed list of the content of eighteen puranas.

[10] Due to a combination of the spendthriftness of his grandfather Vrindavan Mitra and his father's refusal to seek paid employment, Rajendralal spent his early childhood in poverty.

[11] Mitra's education became increasingly sporadic from this point; although he enrolled at Calcutta Medical College in December 1837—where he apparently performed well—he was forced to leave in 1841 after becoming involved in a controversy.

[12] He then began legal training, although not for long,[13] and then changed to studying languages including Greek, Latin, French and German, which led to his eventual interest in philology.

[14][18][19][20] Although Mitra had received little formal training in history, his work with the Asiatic Society helped establish him as a leading advocate of the historical method in Indian historiography.

[25][26] He established the relationship between the Shaka era and Gregorian calendar, thus identifying the year of Kanishka's ascent to the throne,[27] and contributed to an accurate reconstruction of the history of Medieval Bengal, especially that of the Pala and Sena dynasties, by deciphering historical edicts.

[2][28] He studied the Gwaliorian monuments and inscriptions, discovering many unknown kings and chieftains, and assigned approximate time spans to them.

[2][29] Mitra's affinity for factual observations and inferences and dislike for abstract reasoning, in contrast with most Indo-historians of those days, has been favorably received in later years.

He, along with several other scholars, followed a central theme of the European Renaissance that emphasized the collection of ancient texts (puthi) followed by their translation into the lingua franca.

A variety of Indic texts, along with extensive commentaries, were published, especially in the Bibliotheca Indica series,[30] and many were subsequently translated into English.

[2][31] Mitra's instructions for the Pandits to copy the texts verbatim and abide by the concept of varia lectio (different readings) has been favourably critiqued.

Under the patronage of the Royal Society of Arts and the colonial government, Mitra led an expedition to the Bhubaneshwar region of Odisha in 1868–1869 to study and obtain casts of Indian sculptures.

[2][36] The work was modelled on Ancient Egyptians by John Gardner Wilkinson and published in two volumes consisting of his own observations followed by a reconstruction of the socio-cultural history of the area and its architectural depictions.

[49] While many of Mitra's archaeological observations and inferences were later refined or rejected, he was a pioneer in the field[50] and his works were often substantially better than those of his European counterparts.

[55] He published a series of maps of districts of Bihar, Bengal, and Odisa for indigenous use that were notable for his assignment of correct names to even small villages, sourced from local people.

[74] From 1856 until its closure in 1881, Mitra was the director of the Wards' Institution, an establishment formed by the Colonial Government for the privileged education of the heirs of zamindars and other upper classes.

[citation needed] Mitra held the Aryans to be a superior race and wrote numerous discourses covering time spans that were self-admittedly far removed from the realms of authentic history.

A preface of one of his books says: The race [the Aryans] of whom it is proposed to give a brief sketch in this paper belonged to a period of remote antiquity, far away from the range of authentic history; ...

[44] According to Mitra: Countries like Kabul, Kandahar and Balkh from where Muslims had flooded India and had destroyed Hindu freedom, had sometimes been brought under the sway of the kings of the Sun (Saura) dynasty.

[84][85] Renowned polymath Sushil Kumar De has noted that while Mitra's works have been superseded by more accurate translations and commentaries, they still retain significant value as the editio princeps.

According to contemporary news reports, Mitra had endured these fevers for the last few years following a stroke that caused paralysis and grossly affected his health.

Charles Eliot to commemorate Mitra as well as Ishwar Chandra Vidyasagar, who also died around the same time, and was the first event of its type to be presided over by a Lieutenant Governor.

[92] Mitra's academic works along with his oratory, debating skills and miscellaneous writings, were extensively praised by his contemporaries and admired for their exceptionally clarity.

[93] Max Müller showered praise on Mitra, writing:He has edited Sanskrit texts after a careful collection of manuscripts, and in his various contributions to the Journal of the Asiatic Society of Bengal, he has proved himself completely above the prejudices of his class, freed from the erroneous views on the history and literature in India in which every Brahman is brought up, and thoroughly imbued with those principles of criticism which men like Colebrooke, Lassen and Burnouf have followed in their researches into the literary treasures of his country.

[2][96] Rajendralal Mitra has been widely viewed as the first modern historian of Bengal who applied a rigorous scientific methodology to the study of history.

[45][97] He was preceded by historians including Govind Chandra Sen, Gopal Lal Mitra, Baidyanath Mukhopadhyay, Ramram Basu, Mrityunjaya Vidyalankar and Dwarkanath Vidyabhusan; all of whom, despite being aware of the modern concepts of Western history, depended heavily upon translating and adopting European history texts with their own noble interpretations, and hence were not professional historians.

[98][99] Mitra has been alluded to have triggered the golden age of Bengali historiography, that saw the rise of numerous stalwarts, including Akshaya Kumar Maitra, Nikhil Nath Roy, Rajani Kanta Gupta, Rakhaldas Bandopadhyay and Ramaprasad Chandra.