St James's Palace was constructed in 1531 by Henry VIII on the site of a former leper hospital. It originally stood alone within St James's park and hunting grounds. The palace was primarily used for state occasions and the housing of relatives, whilst the Tudor monarchs themselves resided at Whitehall Palace. The palace became the official royal residence in 1702 and continued in use until the 1830s when Buckingham House was constructed.
It has a complex history of alterations and additions. A catholic chapel was added circa 1623 and the house was altered between 1660 and 1727. A major fire in 1809 destroyed much of the original Tudor building and the buildings have been altered various times internally and externally since then.
St James's Palace is still used for accommodation for members of the royal family.
The original Tudor building consisted of a manor house built around four courts and a gate house. The buildings were three-storeyed and the gatehouse had polygonal corner turrets. The original building has been altered extensively but mostly in a Tudor style with crenellated parapets. Some remains of the original Tudor building have survived and these mostly consist of the gatehouse, the chapel royal, presence chamber and parts of the long gallery and other sections of walling.