Henry Thomas Hope was a son of Thomas Hope (1769 - 1831), a wealthy merchant-banker who was described as an "English connoisseur, furniture designer and writer". The Deepdene was the greatest of Dorking’s estates; the 10th Duke of Norfolk built a Palladian mansion on the site in the 1760s, and in 1808 Thomas Hope bought the property, extending it greatly.
Henry (1808-1862) was a politician and patron of the arts, and he further extended the property. There's a fascinating history about the famous Hope Diamond which he inherited, although it turns out that a descendant had to sell it to cover gambling debts. Ultimately Deepdene passed into the hands of the Duke of Newcastle, who let it to the dowager Duchess of Marlborough - her nephew, Winston Churchill, was a frequent visitor.
The estate was broken up in the 1920s and the house became a hotel, but after use by the local railway company during WWII it was ultimately demolished in 1967.
There's much more at http://www.thomashope.org.uk/triumph-tragedy.htm, and a picture of The Deepdene at http://www.exploringsurreyspast.org.uk/themes/places/surrey/mole_valley/dorking/dorking_the_deepdene