St. James’s Palace was built by Henry VIII in the 1530s and was home to several famous sovereigns: Elizabeth I, Charles I and George I, II and III.
These days it plays host to lesser royals, and recently became a base for Prince Charles. (But he now lives at Clarence House, a few feet down the road.) Princess Diana resided here for a while until her divorce in 1996. She then shifted her stuff into Kensington Palace. The only major Royal to retain a room in the palace is Princess Anne.
The area around St. James’s Park was once a medieval leper hospital. Henry VIII then bought it for a significant sum in 1531 and knocked it to the ground. The burial ground (where Green Park stands today) was drained and stocked with deer, and the resulting Palace has been much used ever since.
Mary Tudor actually died here, and Elizabeth I was said to have slept soundly whilst the Armada sailed up the Channel. Charles Ispent his final night sweating in the halls, before being led away for his execution. His nemesis, Oliver Cromwell, then turned it into a prison, before Charles’ son restored its fortunes – along with the monarchy’s.
St. James’s glory days can be dated to the early 18th-century when Whitehall Palace burnt down to the ground. It then took over as the chief residence of the entire Royal Family. Unfortunately another fire in 1809 then demolished everything but the main gate, and George III upped sticks to Buckingham Palace.
The palace was rebuilt soon after but never recovered its former glory, and Queen Victoria formalised the move in 1837.
So, whilst Buckingham Palace remains the official residence of Her Majesty the Queen, St. James’s Palace retains the formal rooms for receptions, weddings and occasions of State. And even today, when foreign dignitaries arrive in London, they are still accredited to the Court of St. James.