A class that once expressed the very essence of Englishness has dwindled to near-extinction in the past century. Political reform and the crippling costs of maintaining a country estate combined to hasten the demise of the gentry and squirearchy. Few survivors of that idyllic existence now remain.

One of these, the Lygon family of Madresfield Court in Worcestershire, has become the subject of a book tracing the history of the family and the house in which it has lived continuously for the best part of a millennium. The fact that the Lygon family became the Earls Beauchamp might seem to disqualify them from membership of the private classes of the gentry. But as the historian David Cannadine points out in his foreword to Jane Mulvagh's history of Madresfield, the Lygons became artistocrats only in the 19th century.

The earldom lasted a little more than 150 years before dying out amid scandal, elements of which were borrowed by Evelyn Waugh for the plot of Brideshead Revisited. The greatest part of the Lygon history is the history of the minor English land-owning classes.

Both Cannadine and Mulvagh point out that the character of Madresfield was both formed and preserved by its situation in what Mulvagh describes as “a rural backwater” in the West Midlands. “An old and particular Englishness lingers [here],” she writes, “an Englishness once captured in different ways by four of its sons: William Langland (author of Piers Plowman), Shakespeare, Elgar and Housman.”

For the structure of her history, Mulvagh takes an almost architectural approach, mimicking the form of the moatencircled house by opening and concluding her account with the story of the Seventh Earl, whose family tragedy provided such rich source material for Waugh's fiction. Within this framing device her narrative is thematic: she fixes on a feature or object belonging to the estate - a ditch, herb garden, breviary or tuning fork - and uses this detail to explore successive eras from the 12th century to the 20th.

Madresfield's claim to fame, apart from the antiquity of its foundations, is its identity as the “real Brideshead”, as opposed to Castle Howard, where the television adaptation of Brideshead Revisited was set. Evelyn Waugh's Oxford friendship with Hugh Lygon brought him as a regular visitor to Madresfield, where he “fell in love with a family”, basing his own great elegy for a vanished style of life on the tragedy that overtook the Lygons when the Seventh Earl was denounced as a homosexual by his brother-in-law, Bend'or, Duke of Westminster, and obliged to flee Britain for Europe, where he remained, disconsolately embroidering chair covers, until his death in New York.

These passages, while the most enthralling in the book, are also the most contentious. “Castle Howard is not like Brideshead at all,” writes Cannadine. Yet Christopher Sykes wrote in his biography of Waugh that “Brideshead has no resemblance to Madresfield, with the exception...of the art nouveau chapel...I fancy that a strong contribution was made by Castle Howard”. There are other slightly doubtful assertions: it is not the case that Waugh was “sent down from Oxford”. He took his finals in the Trinity term of 1924, achieving a third-class degree.

Such minor flaws may lead the reader to wonder if this account of Madresfield is, like the house itself, occasionally shrouded in an artistic mist. Mulvagh is an assiduous researcher and writes in an engaging style of graceful anecdote; in the earlier parts of the history where facts are sparse, she is well able to supply the deficiency with imaginative colour, a quality that also assists her when it comes to describing the Lygons, not all of whom were necessarily either attractive, distinguished or interesting.

And when it comes to recreating the all but vanished life of the English country house and its inhabitants, a certain misty nostalgia is an admirable ingredient.

Extract from Brideshead Revisited by Evelyn Waugh

It was an aesthetic education to live within those walls, to wander from room to room, from Soanesque library to the Chinese drawing room, adazzle with gilt pagodas and nodding mandarins, painted paper and Chippendale fretwork, from the Pompeian parlour to the great tapestry-hung hall which stood unchanged, as it had been designed two hundred and fifty years before; to sit, hour after hour, in the shade looking out on the terrace.

This terrace was the final consummation of the house's plan; it stood on massive stone ramparts above the lakes, so that from the hall steps it seemed to overhang them, as though, standing by the balustrade, one could have dropped a pebble into the first of them immediately below one's feet. It was embraced by the two arms of the colonnade; beyond the pavilions groves of lime led to the wooded hillsides. Part of the terrace was paved, part planted with flower-beds and arabesques of dwarf box; taller box grew in a dense hedge, making a wide oval, cut into niches and interspersed with statuary, and, in the centre, dominating the whole splendid space rose the fountain; such a fountain as one might expect to find in a piazza of southern Italy; such a fountain as was, indeed, found there a century ago by one of Sebastian's ancestors; found, purchased, imported, and re-erected in an alien but welcoming climate.

Madresfield: The Real Brideshead by Jane Mulvagh
Doubleday, £20 Buy the book here

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