The items which are just a fraction of the collection at Longleat House, near Warminster, Wiltshire, were auctioned over two days at Christie's in central London.
Items sold included a 15th century Italian illumated manuscript of the works of Virgil, which raised £1.2m.
The first book ever printed in the English language - published by William Caxton at Bruges in 1473 before he introduced the printing press to England - sold for £600,000.
The copy of Raoul Le Fever's Recuyell of the Historyes of Troye had been expected to fetch up to £400,000.
£1m fox
An 18th century Meissen porcelain figure of a fox raised just over £1m.
All of the proceeds are to be used to help establish a maintenance fund to safeguard the preservation of Longleat House together with its grounds and the remainder of its collection.
Lord Bath, whose family has lived at Longleat for 450 years, said: "It is always difficult to part with such beautiful objects but we were extremely fortunate the items sold constitute only a tiny proportion of the overall Longleat collection.
"I wish the new owners well and am confident every item will be cherished and appreciated by a new generation of collectors and art lovers."
Lions
The Longleat Estate consists of approximately 9,000 acres of land forming one block with the house and park, famous for its lions, in the middle of it.
It includes 4,000 acres of let farmland, 4,000 acres of woodland - which includes a holiday village - and a further 1,000 acres of parkland.
Money from the maintenance fund will provide a vital source of income for future conservation work on the site.
Christie's chairman Lord Hindlip said it was an "honour" his company had been entrusted with the sale.
"It will make a major contribution to the long-term preservation of one of England's treasure houses," he said.