"Russians?" Sir Benjamin Slade pauses, seeking the adjective best suited to the compatriots of Tolstoy and Dostoyevsky. "Dishonest."
"Chinese?" I venture. "They're impossible."
"Brazilians?" "Sex, football and dancing. That's all they do."
"Boring. The Romans described them as boastful. They're at your feet or at your throat."
Sir Benjamin embarked on this guide to global culture after recalling how he once defaced an atlas before presenting it to his godson. "It was this wonderful children's book, showing all the countries of the world and saying lovely things about each. I took this atlas and wrote on every country, all about the people. It is quite horrific, this stuff I wrote, and which the godson read. One of my friends said: 'Do not let anyone see it. Or you will go to prison.'"
"I could wax lyrical about India. I once ran an international shipping business. None of these countries ever pay their bills. I got fed up having to deal with Russians, Indians and things. I mean – have you ever met an honest Russian?"
"I have, since you mention it..."
"You can't have. Like the Arabs – they're a bloody nightmare." We're sitting in the bar at Maunsel House, the stately home near Taunton that Slade, who is childless, has offered to bequeath to whichever stranger can most closely match his family's DNA. The house dates back to the 14th century and has 1,300 acres of land. His proposal, made public in late 2005, was heavily reported in the press especially after Slade, 61, declared that he would not welcome Guardian readers, drug users, communists or homosexuals.
"Gays," he explains, "don't breed. Communists would give the place away."
"Maybe you'd be more at home with a fascist?"
"Hitler was a good socialist."
The seventh baronet, whose family have owned Maunsel since 1772, is equally eager to deter "cowpokes, or people from a trailer park. I want somebody with yachts."
The bar is a stone-floored room whose décor includes stuffed pike, weasels and a large, preserved black widow. The first thing you notice, though, is the unusual number of firearms: several dozen of them. On the window seat, where more sentimental hosts might place a basket of flowers, there is a Bren gun.
"Guardian?" Sir Benjamin had barked, by way of introduction, when I first arrived.
"Same bloody tribe."
Benjamin Slade once famously observed that he "won't do business with any country which has green in the flag, and where they don't wear overcoats in winter". He has real-life challengers for the title of the most right-wing man in Britain, and he is on first-name terms with most of them. (He helped fund John Redwood's leadership challenge in 1995 and says Norman Tebbit is his hero.) But most of Slade's spiritual comrades exist in literature. Men such as Sir Henry Rawlinson, Vivian Stanshall's creation, played by Trevor Howard in the 1980 film Sir Henry At Rawlinson's End: a grotesquely decadent aristocrat whose crest bears the legend "Omnes blotto", Sir Henry defines empire as "decency, democracy, kindness and the occasional necessary mercy killing".
And Sir Benjamin's succinct analysis of national attributes, I tell him, reminds me of an episode of the sitcom Whatever Happened to the Likely Lads, which begins with actor James Bolam assessing the Koreans.
"Not to be trusted," Bolam's character Terry says. "Cruel. Much the same as all Orientals."
"Egyptians?" asks Bob, played by Rodney Bewes.
"Greasy. But not as greasy as the French. I've got no time for the Irish or the Welsh. And the Scots are worse than the Koreans. Come to think of it, I don't like the people in our street very much."
"Well, foreigners think differently to us," Slade says. "It's easier to deal with people from England."
"Do you believe the English are superior to people from Burkina Faso, say?"
"I don't think they are, necessarily. I happen to be English." Slade has a reputation for conviviality. His face, in a certain light, makes you realise what the comedian Tim Brooke-Taylor might have looked like had he spent more daylight hours on licensed premises. He doesn't live here in the main house, where Chaucer wrote The Canterbury Tales; the property – elegantly restored in a variety of period styles – is reserved for weddings, conferences and parties. Sir Benjamin occupies a nearby cottage, which he shares with his partner Kirsten Hughes, the actress who starred with Jasper Carrot in his ill-fated 1987 film, Jane and the Lost City. That movie, in which Hughes, a Rada graduate, inspects a cutlass and remarks: "I say – that's a big one", didn't stretch her dramatic range any more than her other best-known role, as a BA stewardess who could fly without a plane. These days, Slade says, "she does lots of advertising; she went to South Africa to do something for Specsavers".
"She looks a bit younger than you."
"You want a new car," he replies, "you get a new car. Not some old banger."
Slade says he is negotiating with an unnamed terrestrial TV station that will produce a reality show, testing the genes of thousands of would-be heirs against the DNA of his oldest (12th-century) ancestor, William Atte Slade, buried at Cornwood, South Dartmoor, whose remains he intends to exhume.
The recipient of the estate, the value of which has been estimated at between £7.5m and £11m, will inherit a herd of rare White Park cattle and 13 peacocks. Maintaining the property, Slade insists, will be no picnic.
"The annual heating bill is £24,000; insurance is £15,000," he complains. "I've always wished my name was Smith and that I lived in a council house."
It was suggested last year that Sir Benjamin had found a close DNA match in Isaac Slade, singer with Denver-based band The Fray. The 26-year-old has shown no indication of wanting to take on Maunsel, though he has formed an improbable friendship with the baronet.
"Isaac's too busy," says Sir Benjamin. "He is extremely famous. He's sold 6,000,000 albums."
Three years ago, Slade began work on a TV series with a company called Wag TV, which was developing a show based on DNA research, for the Discovery Channel.
"It's hell living in a place like this," Slade told reporters in 2005. "I've got mice. The roof leaks. It's terrible. None of my relatives want anything to do with the dump. They're too bloody rich."
The Wag project, which would have invited 20 likely heirs to Maunsel before gradually eliminating them one by one, came to nothing but the baronet still aims to travel the world to meet some of the 2,000 people called Slade who have contacted him in the hope of establishing the closest genealogical match to his family.
"In America," he says, "there are many Slades in the telephone book. In some areas 90 per cent of them are black; the family that emigrated got friendly with servants. There's a town called Sladeville, in North Carolina. On 4 July there's an annual Slade party in Maryland. I am determined to go. They all write to me."
Having tea with Sir Benjamin, with the sun glinting on the windowpanes and a workman toiling in the next room, I can't help thinking of that line from The Philadelphia Story: "The prettiest sight in this fine, pretty world is the privileged class enjoying its privileges." Meanwhile, the cheerful Polish labourer – hang on – Polish?"
"I've got five Poles and one Slovak. I did have Lithuanians but they smashed things up and got drunk. Two of their women got up the duff. They're in Bridgwater now and their rent's paid by the Government. My Slovakian sends £400 a month back home."
"You're not ideally placed to argue against immigration."
"No. I've got them all working here."
"The EU has been good to you."
"It has. The EU is all right except they pass rules. If you chop down a tree, and there's a horseshoe bat in it, there's no fucking argument: you go to prison."
"And if the tree falls on, say, a great crested newt, you are in even deeper shit."
Since he announced his search for an heir, he claims, he has been asked to lead a tribe in Papua New Guinea.
"The head man emailed because they needed a red-blooded Englishman to procreate with their warrior women."
"How come he's got email?"
"He's the head man. I wrote back saying could he send me photographs and did they still have bones through their noses. I asked him what the hunting was like, and did they eat each other."
Slade was married, from the late 1970s to 1991, to Pauline Myburgh, who he describes as "a good spender".
"Has she remarried?"
"No such luck."
Myburgh still occupies a property which, given a strong arm and a fair wind, is within egg-throwing distance of Maunsel House.
"Did you try to have children?"
"I've been tested. I've got 300 million [sperm, presumably] and 80 per cent are wigglers." He tells me more than I need to know about the alleged gynaecological snags in his marriage.
"When I was divorced, I got very frisky with foreign girls, but they don't fit in down here."
In the 1990s he lived for six years with Fiona Aitken, who later married Lord Porchester, Earl of Carnarvon. ("Grave robbers," Slade says, of her new family.) She, meanwhile, described Slade as: "A cad. I can't imagine why I went out with him. You live and learn."
Cuttings describing Slade's misadventures (often involving animals) are posted around the house. One internet report recently accused Sir Benjamin of purchasing Elvis Presley's teddy bear at auction, then allowing it to be shredded by hounds at Wookey Hole in Somerset.
"I've no idea where that came from. I do not have a bear. The first I knew of it was when I started receiving letters of condolence." Another cutting, relating to Isaac Slade's first visit to Maunsel, reads: "Dog Eats Rock Star's Underpants".
"You were in the national press again recently after one of your peacocks damaged a Lexus."
"He saw this car in peacock blue, in our car park and, being slightly gay, tried to shag it," Slade recalls. "He did £4,000 worth of damage to the bodywork. His name is Ron Davies."
"After the Southampton and Wales centre-forward?"
"After the politician who was caught on Clapham Common doing something so bad no newspaper could print it."
He shows me Maunsel's brand-new, industrial-sized kitchen, its vast marquee and the covered pergola he had constructed in the grounds.
"I can get 200 in the pergola, 400 in the tent. I like lunch parties for 140. In my London house, which I sold because I believed al-Qa'ida was going to take out the capital, I used to have dinners for 43."
"What's wrong with dinner for four?"
"Dinner for four," Sir Benjamin observes, with typical forthrightness, "is wank."
He continues to present the manor, which has 13 bedrooms and costs around £3,000 to rent for a party, as an insufferable burden.
"As I told you, I've longed for a council house."
"Of course you have."
"You," Slade says, "have never had to live in one of these bloody monsters." '
Deprived of the advantages of a council-estate upbringing, Benjamin Slade attended Millfield public school, whose other alumni include Max Mosley, Tony Blackburn and Salem bin Laden.
"That's right. I believe the Bin Ladens were members of White's Club."
"When you were in your teens, your mother, father, uncle and brother all died within four years."
"Yes. One every year. I believe that I wasn't supposed to be born. I popped out of an elderly mother a month early. So instead of being normal, I was slower than the rest."
His older brother Robert died in a car crash aged 20; a couple of years later, when Benjamin was 16, his father Michael died in his arms, here at Maunsel, of a heart attack. Slade was sent to Australia with two letters of introduction. He gives a somewhat romanticised account of his time abroad, where he earned enough on the stock exchange to establish his first serious business: a container company called Shirlstar that would make his fortune. By 1978, it had a turnover of £3m.
"I took dosh out and reinvested. I bought timber mills. I leased out aircraft."
When he was a boy, the house had been in the care of his Uncle Alfred and Aunt Freda. Alfred, he says, "got compensation after troops were stationed here in the war, but he pissed it up against the wall. All Slades," he adds, "liked drinking. Aunt Freda got her hands on the place when I was 15."
Maunsel House became his passion. In 1978 he bought back the then-dilapidated property for £25,000, with Aunt Freda – who, he claims, had repeatedly tried to burn down the property for the insurance – as a tenant, paying £1 a year.
"When she died," he says, "she left about £22.50 and she didn't leave that to me."
If the charm of Slade's self-appointed quest for a DNA heir lies in its parallels with pantomime – the matching Y-chromosome, in this case, fulfils the role of the glass slipper in Cinderella – there are other aspects of his life which, you suspect, Sir Benjamin may be enlivening with a hint of vaudeville. Is Slade really as poor as is often suggested, or has his apparent artlessness evolved in order to mask his significant intelligence, and an unusual ability to turn a profit? Does he really want to give away his estate? Can he possibly be as right-wing as he sounds?
This last question is probably the easiest to answer. When I explained to my host, who speaks of Iraqis as "ragheads", that I'd like to talk to one or two of his friends, he gave me a mobile number for another distressed Devon landowner, Francis Fulford. "Ben is not mad," said Fulford. "He is different. You have people like David Cameron who are afraid to offend. It's important that there are people who, in the euphemism [sic], don't give a fuck."
I tell Fulford that I asked Slade who, in an ideal world, he would like to see leading the Conservatives, and that my question was followed by a very long silence.
"That leader," Fulford replied, "is dead and his name is Enoch Powell. No society in history has benefited in the long term from immigration. Especially of colour. Immigration is a disaster. Powell was my hero. He fought in a war. How many intellectuals ever fought?"
"Fuck-all. How many on The Independent, full of its multi-racial crap? None. Why? Because you're a bunch of cowards."
The reception fades and the background noise alters.
"Where are you going?" I ask him.
"Back to the pub. Everybody," Fulford adds, "should always be in a pub."
"The game's over, for the old Tory militants like you and Slade, isn't it?" I ask him. "You're just dinosaurs."
"We are dinosaurs. Temporarily. As I say to my grandchildren, one day we are going to have to kill those bloody... [Fulford completes this sentence with a phrase that might constitute incitement to racial hatred]. We're going to have to put a machine gun on top of Marble Arch and blast it down the Edgware Road."
"Would Sir Benjamin Slade be at your side?"
"Of course. Feeding ammunition."
Slade's own TV ambitions appear to have been fired by The F***ing Fulfords, a 2004 Channel 4 programme that followed the 55-year-old's struggle to maintain his own disintegrating manor. Sir Benjamin becomes vague when I ask why his own TV project collapsed; insiders say it is because he received what appeared to be a more lucrative offer from another station.
"Did you ever discuss this plan with Channel 4?"
"Yes, says Slade, "but we could never get the right deal. As of now we are negotiating. Hard. Getting a terrestrial to sign is always a problem. We need their money."
"How much does Maunsel House bring in?"
"This year," Slade says, "£320,000. Next year, £500,000. Hopefully, soon, £1m."
"That doesn't sound like the sort of return that would make council accommodation attractive."
"I have to make people aware of the events I organise here. I am determined to out-earn the effing Fulford. His TV programme helped pay school fees. I need to promote myself."
"I was looking through the list of your directorships. You appear to have a wide range of other income sources, including companies that deal with coal, shipping and property. You also own Woodlands Castle [the former home of Sir Alexander Fleming, now a Regency-period conference centre close to Taunton]. And yet recently you said: 'I have diddly squat.' People say you're worth about £20m: is that right?"
"You can't get out of bed with that sort of money, can you?" Slade replies. "£20m is nothing is it, these days? If I want people to hire my house, and I tell them that I own property and have directorships, they go cool on the idea. If you want to make people happy you say... [the baronet adopts the plaintive demeanour of a Dickensian orphan] 'I am absolutely on my uppers. If it wasn't for you having this reception, I wouldn't eat this week.' That makes them so, so happy. We have a chair with its arm hanging down. Kirsten said: 'Don't get it mended. It looks distressed.' And that's what they want: distressed. You can never be too rich. You can never have enough money really."
Any funding for his proposed reality show would need to cover the cost – an estimated £10,000 – of extracting DNA from the exhumed William Atte: that's assuming the church granted permission to disinter, which is far from certain. Then there's the expense of transporting Sir Benjamin to the US ("I must go business class. There's no debate") and the fees for extracting genetic material from the living. "I don't want a few people in a freak show, like The Apprentice," Slade says. "I want thousands."
Then there's the question of exactly what the lucky heir would inherit. Slade tells me that Maunsel would be placed in a trust, "which the successful candidate would run. They'd have life interest in the trust, then pass it on to their children."
Selling off any part of the estate for cash would not, as I understand it, be an option for the winner, which seems to invite the question of exactly how you define ownership. Sir Benjamin, in any case, is adamant that he has had enough of the property.
"I am having a down period at the moment. I am descended from Charles II. I feel I should be doing interesting things. I would much rather be in London, reading, than installing disabled loos, or hearing that a fox has gone and attacked a lamb and bitten its bloody tongue out. I hate agriculture, you know. I loathe it."
Any filming, he adds, "mustn't interfere with Ascot. We're going to have a ball. I am going to be a mega, mega-star. But you have to understand that I believe DNA will rewrite history. I am trying to do something sensible here.'"
Just as we finish talking, Brictwold the Saxon, one of Sir Benjamin's black Labradors, starts barking furiously at a man who appears to be loading tools into a white van, outside the window.
"Gippos," Slade mutters. We stand outside while his uninvited guest, who looks like Johnny Vegas without the charm, drives off.
"Just remember," the man shouts to the baronet as he leaves: "Men meet before mountains meet."
"What does that mean?" Sir Benjamin asks.
"I think it was a threat," I tell him.
Five days later, Slade calls me to report that negotiations with television producers are still under way, and to claim that the van driver had returned at two in the morning, when he broke into an outhouse and started loading up the baronet's lawnmowers.
With the help of Brictwold the Saxon, Slade says, the man was soon seen off. Time will tell whether Sir Benjamin's search for the elusive Y-chromosome will prove quite as straightforward.