Mrs Favell Lee Mortimer, an Englishwoman who started out as a children’s author, published three volumes of travel writing between 1849 and 1854, covering the globe from Asia to Africa to the Americas. She was even-handed, in a back-handed way: she despised just about everyone and everything.

The Portuguese, as well as being “the clumsiest people in Europe”, are “indolent, just like the Spaniards”. The Welsh are “not very clean”; the Zulus: “A miserable race of people”; the Greeks: “Do not bear their troubles well; when they are unhappy, they scream like babies”; Armenians “live in holes in the ground . . . because they hope the Kurds may not find out where they are.” Buddhists, Hindus, Mohammedans: all received a thrashing from the aggressively Protestant Mrs Mortimer.

Lao-Tzu, the father of Taoism, is dismissed as “an awful liar”. Roman Catholicism comes off little better: “A kind of Christian religion, but a very bad one.” Oddly, however, she professes a soft spot for Nubians: “A fine race . . . of a bright copper colour”.

Mrs Mortimer’s guide (which comes out in paperback next month) provides a strange glimpse into the blinkered mind of a middle-class, middle-aged bigot in Middle England in the middle of the 19th century. Her sweepingly negative generalisations and racial stereotyping seem even more remarkable for the fact that this doughty world traveller didn’t go to the places she described and disparaged. The sum total of her foreign travel was one childhood trip to Paris and Brussels. Her knowledge of Taoism was exactly zero. She had never set eyes on a Nubian. She amassed her pungent prejudices sitting in her English drawing room.

This was once an acceptable British way to travel (or, more exactly, stay at home and not travel). Mrs Mortimer’s all-embracing xenophobia was probably extreme, but it was far from unique. Those sorts of casual prejudices were part of the arrogance of empire, but also reflected a deep-seated insecurity. Mrs Mortimer was terrified of anybody un-English because she stayed in England.

Other countries have chauvinists, but the blanket disdain for Johnny Foreigner was a peculiarly British phenomenon. “Don’t go abroad,” muttered George VI, speaking for his class and most of his realm. “Abroad’s bloody!” Nancy Mitford’s Uncle Matthew ventured abroad once, but “four years in France and Italy between 1914 and 1918 had given him no great opinion of foreigners . . . ‘Frogs are slightly better than Huns or Wops, but abroad is unutterably bloody and foreigners are fiends’.”

There is a delightful line in Gosford Park, when one snobbish British character turns to his weeping wife and hisses: “Would you stop snivelling? One might think you were Italian!” It is a remark that perfectly blends snootiness, stiff-upper-lippery and ignorance. Evelyn Waugh, so acute on so many subjects, was capable of travelling with his eyes closed: he sneered that, from the air, Paris without the Eiffel Tower looked like an extended High Wycombe.

Cheap and plentiful foreign air travel may be killing the planet, but at least it has finally killed off the sort of prejudice that was once the hallmark of the British armchair traveller. Britons today wander in vast droves, and are informed about Abroad in a way that would have been entirely foreign to our grandparents. Mrs Mortimer insisted that the English “like best being at home, and this is right”. Today the English like best being on a cheapo flight bound for somewhere as far from home as possible. And this, it seems to me, is right.

The World Cup will bring with it the usual bout of soul-searching when some sunburnt, beer-drenched oik insists on performing the “Don’t mention the war” sketch in downtown Munich. But if this is xenophobia, it is a pale, ironical imitation of the deeply ingrained aversion to foreign folk that once prevailed in our culture.

Racism persists, but gone is the fear of foreignness. The British are as likely as ever to complain that the French smell of garlic and the Germans have no jokes. The difference is that the vast majority of Britons know the stereotypes are not true. We no longer laugh with Mrs Mortimer — as she points to the clumsy Portuguese and the scurvy Greeks — but at her.

No politician could now declare, as the Earl of Crawford, a former Tory Cabinet minister, did in 1929: “I am a xenophobe, particularly as regards the French. I look upon France as a corrupt and corrupting influence, and the less personal intercourse between Britain and France the better.”

The Second World War reinforced that sense of superior isolation. The MI5 officer responsible for interviewing suspected foreign agents during the war compiled an official report offering observations such as “Italy is country populated by undersized, posturing folk”. He was not joking.

For some time after the war, the British island mentality meant defining our nationality in contradistinction to others. “For the English,” David Frost and Anthony Jay once wrote,“the best definition of hell is of a place where the Germans are the police, the Swedes are the comedians, the Italians are the defence force . . .”. Today, according to Crap Towns, the best English definition of hell is Hull.

We owe Mrs Mortimer a debt, for her little book is the shining example of how not to travel in the British manner, a reminder of a way of thinking that has gone forever.

Mrs Mortimer wrote her own epitaph: “They always laugh when they hear of customs unlike their own; for they think that they do everything in the best way, and that all other ways are foolish.” Was this some sudden flash of self-knowledge? No, this is Mrs Mortimer, sticking the boot into the Bechuanas of South Africa.

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