The astonishing collection of 200 photographs was the work of a Scottish doctor, John Murray, who took up photography in the 1840s when the art form was in its infancy.
Until now, the archive has remained in the hands of Dr Murray's family. Many of the photographs have not been seen for generations and bidding is likely to be fierce at Sotheby's in London on 18 June.
Dr Murray lived in Agra for 20 years. He devoted his time to trying to find a cure for cholera. But he also took a great interest in the Taj Mahal, making a point of showing it to visitors at night, when it was illuminated with blue lights.
He took up photography in 1849, only 10 years after it had been invented in Europe, and from then on pursued his new hobby with as much dedication as he practised medicine.
Indeed, when Dr Murray's photographs were published in London by Joseph Hogarth in 1857, a review in The Morning Post said: "These views are not tinted: they are monochrome studies, now golden brown, anon of a rich reddish sepia hue, now grey and lucid, presently almost of a black Indian ink lustre, but still, in one form or another, monochromes, and as such remarkable for richness, mellowness and a beautiful modulation of shade and tone."
Mark Haworth-Booth, curator of photographs at the Victoria and Albert Museum, which currently has a triptych of the Taj Mahal taken by Dr Murray on display, describes him as a pioneer of photography.
"He certainly took the first important pictures of India. His photographs are extremely good.
"You can immediately tell that he knew where to put the camera to get the best shot and he was also very good at the technical details. His photos are not just black and white but they have very subtle tones."
Dr Murray was born at Peterhead, near Aberdeen, and after completing his medical studies in Edinburgh and Paris he sailed to Calcutta as an assistant surgeon for the East India Company.
In 1848 he was appointed Civil Surgeon of Agra and played an active role in the creation of the Thomason Hospital and Medical School.
Lydia Cresswell-Jones, of Sotheby's, said: "He was primarily a doctor who was determined to find a cure for cholera but once he had discovered photography he spent a lot of time doing that.
"He organised a system of dispensaries and also advocated that patients should be isolated whenever there was an outbreak."
Ms Cresswell-Jones said Dr Murray was the first person to have systematically recorded the four major historic sites at Agra, Mathura, Sikandra and Fatehpur Sikri.
The secrets of photography were released to the world in 1839 after an Englishman, William Henry Fox Talbot, and a Frenchman, Louis Jacques Mande Daguerre, arrived at the same end result using different methods.
Photography quickly became fashionable and a sign of status among the professional classes, who could afford the expensive equipment. New pictures were written about with all the intensity of film reviews today and Queen Victoria and Prince Albert would often go to photographic exhibitions.
"Cameras were very expensive to start with and as a hobby photography remained the preserve of the professional classes for several years," said Mr Haworth-Booth. "But in the same way that early computers were used by mathematicians, so cameras tended to be adopted by doctors because they had a good grounding in science and could understand the chemical reactions needed to develop the pictures."
The 1850s were known as the Era of Conceptual Photography because of the amount of planning and equipment needed to arrange a shoot.
"You couldn't just wander along and take a snap. You had to have the idea first and nothing was left to chance. It was a very long-winded process in those days and he would have had to transport a dark tent - so that he could process the images on the spot - as well as all the chemicals and equipment."Reuse content