The building was built between 1824 and 1927 under the direction of Sir Robert Smirke, the leading Greek revivalist architect and designer of both the Royal Opera House and the British Museum.
The building was used by The Union Club, one of the first gentleman's clubs, and by the Royal College of Physicians. The Union Club was set up in 1805 and the Duke of Wellington and Charles Dickens were members. It was somewhere for upper class gentlemen to drink, smoke, and gamble.
The High Commission of Canada acquired The Union Club on the south side of the building in 1923 as Trafalgar Square was actually known as 'Little Canada' at the time. King George V and Queen Mary attended the official opening on 29 June 1925.
The High Commissioner's office was The Union Club's gambling room and The Union Club's logo can still be seen on the fireplaces. King George V was heard to say how jealous he was as the room was better than any office in London including his own! The room is opulent with gold detail on the ceiling and crystal chandeliers. The room has furniture from the seventeenth century and a plush carpet which was so large it had to come through the window and Trafalgar Square had to be closed while it was lifted into the first floor room!
In 1963, the premises of the Royal College of Physicians were obtained, enabling the High Commission to expand to occupy the whole of the west side of Trafalgar Square. Building work took place to convert the two buildings into one.
The building gradually deteriorated until in 1993 it was closed and there were plans to sell it. But there was a stipulation on the lease which stated the building had to be refurbished to be sold so it was decided to refurbish and then keep the building, after such a large expense (£6.8 million).
In May 1998, 73 years after her grandparents officially opened Canada House, Queen Elizabeth II did the honors for the grand reopening.
Visit the web site of the Canadian High Commission in London.