Cash-hungry Blairs put in the shade by lavish lifestyle of our first Prime Minister

He had nine homes, an art collection fit for a king, and a cellar awash with fine wines. Severin Carrell reports on a discovery that has shed amazing new light on the life of Sir Robert Walpole

Documents published today by the National Archive detail for the first time the staggering opulence of Britain's first Prime Minister, Sir Robert Walpole, a man whose taste for fine wines, Old Master paintings and vast expenditure leaves the Blairs looking threadbare by comparison.

Historians are delighted by the discovery of hand-written papers that open up previously hidden chapters of Walpole's life. They also give a rare "below stairs" snapshot of early Georgian Britain.

Sir Robert had nine homes in his native Norfolk and London, and every stick of furniture and piece of crockery is listed. The papers also list his huge collection of Old Masters, including works by Rembrandt, Leonardo da Vinci, Titian, Michelangelo and Rubens, alongside his vast wine cellar and his remarkable collection of at least 260 pineapple plants.

Sir Robert became a Whig MP in 1701 and, after holding a series of government positions, was simultaneously appointed Chancellor of the Exchequer and First Lord of the Treasury in 1720.

In effect Britain's first Prime Minister, he served for nearly 21 years under both George I and George II, and became the first premier to occupy Downing Street.

The inventory, compiled soon after his death in 1745, was used during a bitter court battle in the 1760s between his surviving relatives over the ownership of his estate. They were uncovered by a research student, Penny Winstanley, during a mammoth exercise by the National Archive at Kew to catalogue two million Court of Chancery records dating back to 1353.

Walpole's great wealth was a cause of snide remarks by contemporary critics. The wine collection at his St James's Square home ran to "41 dozen pint bottles of Cyprus [a wine] ... 63 dozen pint bottles of Sack [a Spanish or Canary Islands white] ... 11 dozen bottles of cyder in quart bottles ... 11 dozen and two pint bottles unknown".

The "Houghton plate", a set of silverware used at the family estate, weighed in at 6,942 troy ounces, nearly 220kg. The silver included a 10-branched candlestick, scalloped basins, dishes and tureens, and was valued at £1,851 and eight shillings - a fortune by modern standards.

The "green velvet state bed chamber" at Houghton Hall, a vast Palladian mansion built for Sir Robert near his birthplace, included: "A green four-post lath bottom velvet bed lined with lustring [a glossy silk fabric] trimmed with gold lace richly embroidered with gold and valance fringed with ditto ... carved and gilt frames with green velvet covers and gold lace ... one pair of green velvet window curtains, lined with lustring embroidered with gold lace ... [and] a six leafed India screen."

By contrast, his servants' dormitories were spartan. The 14 beds, sheets, pillows and bolsters, assorted furniture, "fire tools" and mirrors fetched a much more modest £33 and 15 shillings.

Other entries record "exotick" plants, valuable window panes and mirrors, a rare eight-day clock made by a famous local clockmaker and a "very large diurnal telescope" in the "closet" at his house at Richmond Park.

Sir Robert never travelled abroad, but thanks to tours in Italy and Holland by his sons and his brother, he amassed a significant Grand Tour collection. Other paintings were gifts from ambassadors and the ambitious to curry favour.

He acquired a reputation as a leading art collector of his age, and his best Old Masters were later sold to Catherine the Great of Russia. They now belong to the Hermitage museum in St Petersburg.

Andrew Moore, an expert on Walpole and keeper of art at Norwich Castle Museum and Art Gallery, said: "It's a remarkable picture, in fabulous detail, of the social and domestic life of the Prime Minister and his family ... It is also a wide-open window on the life of the period."

The inventory helped Sir Robert's estate pay off his substantial debts. He died owing what was then the enormous sum of £40,000.