Recession or no recession, money is again being lavished on doing up houses to the nines — at least in such rich parts of Oxfordshire as the Cotswolds, where it sometimes seems that whole villages are being polished up, inside and out. Much of it is City money, I am told — all those bonuses finding their way back into the economy — and much of it is foreign money; but I would venture that in this last respect little has changed over the past 80 years or so, or even longer.

It took a patrician American to lead the way in dragging splendour, brightness — even a sense of theatre — back into grand, but all-too-often rotting, English country houses, and into their gardens too. And it was at Ditchley Park, in Oxfordshire, that Nancy Lancaster, with the help of John Fowler, began the business of breathing new life into old houses.

Virginian-born Nancy Lancaster (1897-1994), the owner of interior decorating company Colefax & Fowler, came to England as early as 1915 to stay with her aunt Nancy, the wife of William Waldorf Astor, later second Viscount Astor, at Cliveden, Buckinghamshire. Here she impressed biographer Lytton Strachey among others with her enthusiasm for furniture and fabrics, and with her fresh approach to the business of restoring houses, particularly 18th-century mansions.

In 1919, she was back at Cliveden, as widow of Henry Field, heir to an enormous fortune garnered from the Chicago department store Marshall Field. On the ship crossing the Atlantic she met a cousin of her late husband, Ronald Tree (1897-1976), who had been brought up and educated in England. Soon afterwards, they were married.

First, the fabulously wealthy pair lived in a New York house rented from architect Ogden Codman, the co-author with Edith Wharton of the hugely successful The Decoration of Houses; then they bought and restored Nancy’s grandfather’s old house in Virginia, called Mirador; and then, in 1926 they returned to England to set about restoring houses here in real earnest.

Shortly before the Second World War they bought Ditchley Park, near Enstone, from the Lee Dillon family — who had owned it for some 400 years. It had been designed by James Gibbs — who also designed the Radcliffe Camera — but had latterly been allowed to deteriorate to such an extent that the 17th Viscount Dillon, the vendor of the house, washed in a zinc tub in front of a fire in the Great Hall. It also came complete with an estate of 3,000 run-down acres.

Here Nancy joined forces with John Fowler (1906-1977) who was on the threshold of his career as a decorator, having joined forces with the London society hostess Sybil Colefax in 1938. (Her home in Chelsea, incidentally, became known as The Lions’ Corner House, because so many VIPs were lionised there!) John Fowler came from a very different background to Nancy Lancaster. His father deserted the family when he was nine and he left school at 16. But the partnership, though sometimes stormy, flourished. They set out together to buy furniture and to commission artists such as George Oakes to design wallpaper — and they established what has ever since been known as the English country house look. They even created a language of colours that included such unappetising titles as ‘dead salmon’, ‘mouse’s back’, ‘caca de dauphin’, and ‘vomitesse de la reine’.

She also employed Geoffrey Jellicoe to lay out the sunken Italian Garden at Ditchley, a piece of work that prompted interior designer David Hicks to call Nancy Lancaster “the most influential English gardener since Gertrude Jekyll”.

Sadly, after the war, Nancy’s marriage to Ronald Tree came to an end; but in 1954 she bought Haseley Court, in Great Haseley, not far from Thame, where she and John Fowler again collaborated. As for Ronald, he married American socialite Marietta Peabody. Their daughter was the model Penelope Tree.