It is said that, there was a time when the Armenians were the pivot of the city of Calcutta. They owned trading companies, publishing houses, associated with shipping lines and had big trading businesses, like indigo, shellac and jewellery. With European heritage, enterprising attitude and untiring efforts, they changed their fortune and also found easy access to the coveted government jobs. Added to it, they also owned prime real estate in the city. In fact, the Armenians constructed many massive and breathtakingly beautiful mansions in Calcutta.

Among the illustrious Armenians, the name of Johannes Carapiet Galstaun is most likely to rank top of the list. Born in Iran in 1859, he arrived at Calcutta at a tender age for better education. In Calcutta, he was duly enrolled in the Armenian Philanthropic Academy, now known as the Armenian College and later went to St. Xavier's for higher education. Gradually, with the passing of time, he made a mint of money with his enterprising efforts, diligence and intelligence. He became famous as a real estate tycoon and horse racing enthusiast. In fact, it can be easily concluded that, no account of horse racing in India would be complete without mentioning the name of Johannes Galstaun. He was a man of modest attitude, but had the dignity to rub shoulders with the princes and monarchs. Unfortunately, though he made a fabulous fortune from real estate and racing, he virtually lost all of it on the racing turf.

As it is already mentioned, Galstaun built several massive mansions in Calcutta, designed with some degree of luxury, especially for the use of the European residents. One of the most celebrated among these is the Queens Mansion and the other one is the Nizam Palace, standing tall with its five crowning domes on AGC Bose Road, near the crossing of Camac Strreet, which he built as a token of love for his wife and named it Galstaun Park.

Located on a corner plot at the crossing of Russel Street and Park Street, Queens Mansion was originally known as Galstaun Mansion. The huge edifice was built in the year 1920 at a cost of Rs 650,000, an amount which was considered to be very lavish for a single building at that time. It has apartments on the upper floors and commercial establishments at the ground level. During those days, the mansion offered splendid views of the city of Calcutta, along with the flowing River Hooghgly beyond, from its rooftop. The massive dual blocks of the six storey building are joined at the corner of the street.

The exterior of the massive building is definitely larger than life, maybe not architecturally, but definitely in size and shape. In fact, Galstaun Mansion represents a time of transition, when the outer look of a building with intricate ornamentation was giving way to functionality and necessity, when the engineering and utilization of a building were becoming more important than its aesthetic appearance. Materials and techniques began to dictate the look of the buildings, in ways more functional than aesthetic. But one thing is for sure, the enormous Galstaun Mansion and many other such grand edifices, built in that period, bear the testimony to the wealth and supremacy commanded by the Armenian community in Calcutta during the British rule. People like JC Galstaun, Arathoon Stephen and TM Thaddeus changed the cityscape and contributed much to the architectural map of Calcutta.

Galstaun Mansion was built on the very site, where once stood the residence of Sir Henry Russell, after whom both Russell and Little Russell Streets were named. This is the same building in which Rose Aylmer died, whom the poet, Walter Savage Landor immortalized in the inscription on her grave in the South Park Street Cemetery. Rose Aylmer, a carefree girl of 17, who used to stroll with Walter Landor on the mountains and shores of Wales, died of cholera at the tender age of 20, within a year of her arrival in Calcutta.

In 1924, Bengal Club purchased several chambers in the Mansions, for use of their members. But, since the rooms remained vacant most of the time, the club was forced to sell them off. The club also maintained a caterer's kitchen here for a brief period, called Heinche's Kitchen. The arcade of this grand building accommodated many famous names of those days, like Oriental Gas Company, who were the first to light up Calcutta's streets, Mirta Lina, specialist in ladies garments, master tailors Barkat Ali & Brothers and Sahni & Sons, reputed jewellers Satramdas Dhalamal, Magnolia Restaurant, where Pat Tarley belted out Pop songs in her inimitable style, Chemould Art Gallery, Castlewoods, where the IFA shield would take temporary shelter to get its coat of yearly polish, Harmony House, dealers of musical instruments and electrical appliances, hairdressers AN John and Middleton Engineering. The Imperial Bank of India also had an office in this building. Some of the concerns, as mentioned above, have vanished with time, while many others are still there.

In 1953, Galstaun Mansions was renamed as the Queen's Mansions to mark the coronation of Queen Elizabeth.