Marlborough House is a mansion in Brighton on the south coast of England. It is a Grade I listed building. Located at 54 Old Steine, it was built as a red brick building c. 1765 for Samuel Shergold, a local hotelier. After being sold on by both Shergold and its second owner, the Duke of Marlborough, in 1786 it was bought by William Gerard Hamilton and altered to a Georgian design by Robert Adam. For many years it was owned by Brighton and Hove Council. It is currently undergoing major renovations.