On the ground it is hard to get a measure of the Crichel Estate in Dorset. It takes in almost 10,000 acres, in the glorious countryside to the north of Poole harbour, near Wimborne Minster. As someone currently contemplating whether the benefits of an extra 7ft of London garden and a 10x8ft bedroom might really be worth another £100,000 of mortgage, I'm finding property on this scale quite tricky to assess.

I try walking its perimeter, but I don't get far. In the end I find I can get a better indication of Crichel's extent from an aerial view on YouTube: in a short film advertising the hunting possibilities of its thousands of acres, a helicopter- mounted camera swoops for several minutes around the gentle hills and valleys of the property, before dwelling on the main house itself. Crichel is a great Palladian pile that provided the backdrop for the 1996 film adaptation of Jane Austen's Emma, starring Gwyneth Paltrow. It was mostly built by John the Bastard, one of the noted Bastard brothers of Blandford Forum, in 1742. Its land includes three villages, a cricket club, a church and a school. All of this could, apparently, now be yours for around £100 million, making it the most expensive British property outside London ever sold.

But as with all such sales, this one – if it happens – will be magnificently discreet. Nobody in the villages on the estate seems to know for certain if the great house or land on which they live is even being offered for sale at all, though rumours have been widely reported. Some suggest – hopefully – that the property has attracted the interest of Prince Charles (who owns neighbouring land) and who "would perhaps like to purchase it for his son and his new bride"; others believe it will go to this or that oligarch to fulfil their increasing desire for English dachas to go with their London mansions; and rock stars have owned some of the land around here in the recent past – Greg Lake of Emerson Lake and Palmer had the next-door property. But it is the members of the global financial elite who can most likely afford estates like this now.

Over the past decade or so, prime land and property in Britain has increasingly shifted from ownership by those with inherited wealth to the beneficiaries of the long boom in the world's money markets that ended in 2008. In 1980 there was a 70% likelihood that the buyer of a property such as Crichel House – or Cliveden, former seat of the Astors in Buckinghamshire and now on the market for a cool £35 million – would owe their fortune to inheritance. By 2007 that likelihood had dropped to about 11%. One consequence of globalisation has been that prime chunks of British property have been sold off from beneath our feet, as it were, to those whose wealth is offshored and whose property portfolio probably also includes a place in the Alps, the Caribbean and Dubai. Now 60% of London properties worth over £2.5m are owned by foreign investors. And the trend has spread to the country. The steel magnate Vladimir Lisin paid £6.8m for the 3,300-acre Aberuchill Castle estate in Perthshire. Boris Berezovsky bought 172-acre Hascombe Court, near Godalming in Surrey, for £10m. Roman Abramovich paid £12m for Fyning Hill, near Midhurst in West Sussex, which came complete with a personal playground of go-kart track, clay-pigeon shoot, trout lake and rifle range.

When Leon Max, a Russian-born fashion retailer, bought the 600 acres of Easton Neston in Northamptonshire for £15m in 2008 from the formula one boss Lord Hesketh, he commented that "I like the idea of being a country gentleman… I am looking forward to shuffling to my atelier in my monogrammed slippers". He is rivalled by Stefan Persson, 61, owner of H&M, who owns an 8,500-acre shooting estate in Wiltshire and the 1,500-acre Linkenholt estate near Andover in Hampshire. We sell costume drama to the world and increasingly the world – or at least that tiny percentage of it that counts its wealth in seven figures – buys a contemporary version of it back, mostly tax free and with a bit of deference and a state-of-the-art cinema room thrown in. Like Persson, Max has learned to shoot, has adopted corduroy Savile Row suits and entertains the local hunt.

Places such as Crichel House and Cliveden were built to show off the taste and trappings of the home-grown elite of past centuries, men who owed much of their wealth to the exploitation of labour and resources in distant corners of the globe. In colonising English estates now, you could say the globe is returning the compliment. It is apparently becoming hard to put a price on the "authentic experience" of the British aristocracy. At hedge fund billionaire Arki Busson's charity ball last month one diner bid £250,000 for a weekend break at Blenheim Palace. The traditional aristocratic season of Ascot, Henley and Wimbledon, its rituals of dress and insouciance, is embraced by the global elite with similar mesmerising extravagance.

One thing that this elite may not embrace as it buys up British land, however, is the traditional conscience-salving relationship that has existed between Britain's historic landowning families and their tenant farmers and tied cottagers. The villages of Witchampton and Moor Crichel may be sold with Crichel House. The people who live there now exhibit an understandable anxiety not only at the prospect of a new landlord, but also at the consequences of saying anything out of turn.

That anxiety seems a historical relic – like something out of Thomas Hardy or Jane Austen or even Piers Plowman – but it is real enough. One man I ask, a resident of neighbouring Cranborne, speaks to me under condition of anonymity. He describes how "this part of the world is still made up of country estates and has not changed much since Norman times and feudalism. Many of the landowners can be traced back to Norman ancestors, when Anglo-Saxon England was carved up by the invaders from Normandy. Some of the working families in Witchampton, likewise, are mentioned in documents dating from the time of Henry VIII. To live here is to experience what life was like 200 years ago." It is that experience, with added swimming pools and helicopter pads, that makes these places so attractive to buyers who have done their homework watching Gosford Park and Brideshead Revisited. The local man went on to express the hope that "the next owner of Crichel will at least retain the current workforce (who live in "tied" accommodation – no job, no home) and maintain the area's unique charm…"

Russians bearing guns, attracted to Crichel's renowned pheasant shooting, may not be particularly welcome, especially as they will tend to spend only a small part of their time at the house. Celebs would probably be worse. "The last estate up for sale in Dorset was in the Purbecks," my informant tells me. "This was bought by a financier after being viewed by Kylie. Cecil Beaton's home, just over the border in Wiltshire, was bought by Madonna. What benefit was there to the local economy in having Madonna here? Hardly any. She brought her own entourage with her, who sourced most of the workmen and domestic staff from elsewhere. To stop cameramen photographing her house from the air, she bought up the local airfield. Her staff would try and hire restaurants for the entire evening, to exclude locals and regulars, just for herself and her cronies. Luckily they put their loyal customers before financial greed – Dorset is not a 'Material World'…" – or at least not entirely.

One of the REASONS the British can no longer always compete to buy their own land, and why that land and property is such a safe bet for foreign investors, is coincidentally rooted in the history of Crichel House. In the "Battle of Crichel Down" of 1954, the Napier-Sturt-Marten family, who had owned the estate for 500 years, took on Churchill's postwar government to have returned to their ownership a piece of land that had been compulsorily purchased by the RAF for bombing practice during the war. The stand-off was seen as the last redoubt of the aristocracy against parliament, and the aristocracy won. The "integrity" of the Crichel estate was restored and the government minister who had fought that losing battle, Sir Thomas Dugdale, famously resigned. Thereafter any question of land reform, of the breaking up of ancient estates for the common good was shelved.

The vast majority of land in Britain has a similar kind of "integrity", rooted in the covenants of the Domesday Book. One of the effects of that 1,000-year status quo is to make British houses, on average, the most expensive and the smallest in Europe. Another is to ensure that, because of the scarcity of land available, estates will always be a stellar investment to those who can afford to maintain them. Kevin Cahill's book Who Owns Britain sets out the figures pretty starkly: the UK is 60m acres in extent, and two-thirds of it is owned by 0.36% of the population, or 158,000 families. A staggering 24m families live on the 3m acres of the nation's "urban plot" – and not surprisingly buy into the idea that Britain is a severely overcrowded country in which land is extremely scarce.

It is not quite so scarce if you happen to be the descendant of the "cousinhood" of aristocracy who carved up the nation in feudal wars or at the gambling table – or through grace and favour, and profits from slavery – and whose offspring have until recently doggedly preserved their thousands of acres from almost every subsequent threat of disbursement (if only, in some cases, to sell them intact to Russian steel magnates or Swedish T-shirt sellers). Among the diehards are the current Duke of Buccleuch, with his 240,000 acres; the Duke of Northumberland, who owns 131,000 acres; and the Duke of Westminster, with 129,000 acres taking in much of Belgravia, as well as the centre of Liverpool. To them, you imagine, the country doesn't look very crowded at all.

Carol Wilcox, secretary and treasurer of the Labour Land Campaign, has one antidote to this persistent sense of England as a playground for the super-rich. She recently drove from her home in Christchurch down to the Tolpuddle Martyrs' Festival in Dorset. Her route took her along an ancient brick wall which seemed to go on for ever and, as she drove along the A31, she recalls, she was getting more and more furious about it. "What's all this, built to keep the peasants out?" she wondered. At Tolpuddle she discovered that the wall was, in fact, the longest continuous structure in England, incorporating two million bricks, and that behind it lived the MP for South Dorset, Richard Grosvenor Plunkett-Ernle-Erle-Drax, who David Cameron likes to call Richard Drax. The estate is open to the public on two days a year, when the villagers make tea and cakes.

"It is just feudal, still, all this," Wilcox suggests. She got interested in land reform when she read Mervyn King's book on British tax. There seemed to be a glaring omission in it: land value tax. Rather than taxing income so heavily, or seeing aspiration to ownership taxed in the form of stamp duty, why not impose an annual tax on the productive value of land per acre (excluding occupied homes in the lower council tax bands), and thereby address the most glaring inequity in the country? This might allow tenants of all kinds to finally own a little patch, leading to the eventual disbursement, at fair price, of some of the millions of acres currently held in a few thousand hands. And it would mean the 40% of prime property currently being sold to often absent foreign investors would not look quite so attractive.

"I like to think about the effects of not taxing land," says Wilcox. "House prices remain unaffordable; there is a vast amount of wasted land, derelict sites and empty property in the hands of an elite few; and nearly all private income that could be used for investment goes on servicing property debt, allowing the banks to make their massive gains. The only reason anyone should own land is to use it…"

The idea goes back a long way, to Thomas Paine through Lloyd George. Andy Burnham, the Labour leadership candidate, had it as a plank of his manifesto, but Ed Miliband, according to Wilcox "seems not to get it". Vince Cable put forward a version at last year's Lib Dem conference when he suggested that a progressive alternative to attempting to raise tax on global capital, routinely offshored, "is to shift the tax base to property, and land, which cannot run away, [and] represents in Britain an extreme concentration of wealth". Traditionally whigs and Tories have clashed over land reform; you wonder if, as finances squeeze still further, that might be the fracture line again.

Britain is, of course, full of complicated nostalgia for the world of stately homes and manicured lawns, and the opposition to such a change is deep rooted, even among those it might benefit. Wilcox is fed up of hearing how the great landowners are custodians for whose stewardship we should be eternally grateful. You can hear it in the anxieties of the tenants and villagers in Dorset, who place their hope in a benevolent landlord, rather than in a stake in the ground.

As Britain's estates change hands, it is doubtful whether similar loyalties will be extended to foreign owners flying in for the grouse season. Behind their high walls, however, once they have purchased a piece of "authentic" heritage, the new owners of British acres probably won't worry too much about what the natives think. They will be too busy humming those famous old verses of Noël Coward: "The stately homes of England/How beautiful they stand/to prove the hedge fund billionaires still have the upper hand/though the fact that they have to be rebuilt/is a small price to pay to wear a kilt/and much more fun than buying gilts… ( to fade)".