No language has spread as widely as English, and it continues to spread. Internationally the desire to learn it is insatiable. In the twenty-first century the world is becoming more urban and more middle class, and the adoption of English is a symptom of this, for increasingly English serves as the lingua franca of business and popular culture. It is dominant or at least very prominent in other areas such as shipping, diplomacy, computing, medicine and education. A recent study has suggested that among students in the United Arab Emirates "Arabic is associated with tradition, home, religion, culture, school, arts and social sciences," whereas English "is symbolic of modernity, work, higher education, commerce, economics and science and technology." In Arabic-speaking countries, science subjects are often taught in English because excellent textbooks and other educational resources are readily available in English. This is not something that has come about in an unpurposed fashion; the propagation of English is an industry, not a happy accident.

English has spread because of British colonialism, the technological advances of the Industrial Revolution, American economic and political ascendancy, and further (mostly American) technological developments in the second half of the twentieth century. Its rise has been assisted by the massive exportation of English as a second language, as well as by the growth of an English-language mass media. The preaching of Christianity, supported by the distribution of English-language Bibles, has at many times and in many places sustained the illusion, created by Wyclif and Tyndale and Cranmer, that English is the language of God.

The history of English’s global diffusion is littered with important dates: the planting of the Jamestown colony in 1607; Robert Clive’s victory at the Battle of Plassey in 1757, which ushered in the dominion of the British East India Company; the creation of the first penal colony in Australia in 1788; the British settlement at Singapore in 1819 and establishment of a Crown Colony in Hong Kong in 1842; the formal beginning of British administration in Nigeria in 1861; the foundation of the BBC in 1922 and the United Nations in 1945; the launch by AT&T of the first commercial communications satellite in 1962. This list is condensed. It takes no account, for instance, of the various waves of Anglomania that swept much of Europe in the eighteenth century. But it will be apparent that the diffusion of English has had a lot to do with material reward, the media, and its use as a language of instruction. A fuller list might intensify the impression of a whiff of bloodshed.

Wherever English has been used, it has lasted. Cultural might outlives military rule. In the colonial period, the languages of settlers dominated the languages of the peoples whose land they seized. They marginalized them and in some cases eventually drove them to extinction. All the while they absorbed from them whatever local terms seemed useful. The colonists’ languages practised a sort of cannibalism, and its legacy is still sharply felt. English is treated with suspicion in many places where it was once the language of the imperial overlords. It is far from being a force for unity, and its endurance is stressful. In India, while English is much used in the media, administration, education and business, there are calls to curb its influence. Yet even where English has been denigrated as an instrument of colonialism, it has held on – and in most cases grown, increasing its numbers of speakers and functions.

In the early decades of the twentieth century, H.G. Wells imagined what would become known as World English in his prophetic novel, "The World Set Free." That term for the concept of English as an international language, a global second language, an intellectual and commercial lubricant, even an instrument of foreign policy on the part of the major English-speaking nations, grew common only in the 1960s. It has circulated since the 1920s, though, and the idea was touched upon earlier, not just by Wells, but also by Alexander Melville Bell, who had in 1888 presented World-English, a scheme of revised spellings intended to help learners acquire the language that, as he saw it, exceeded all others "in general fitness to become the tongue of the World." Robert Nares, writing in 1784, presented with no little relish a vision of English extending prodigiously around the globe. Even before that, John Adams had prophesied that it would become the most widely spoken and read language – and "the most respectable."

The term World English is still in use, but is contested by critics who believe it strikes too strong a note of dominance. Today World English is known by several names, perhaps the most catchy of which is Globish (though personally I think this sounds silly), a term popularized by Jean-Paul Nerrière in his book “Don’t Speak English, Parlez Globish." Globish, as conceived by Nerrière, is a pragmatic form of English consisting of 1,500 words, intended to make it possible for everyone in the world to understand everyone else.

Nerrière’s Globish is not alone. Madhukar Gogate, a retired Indian engineer, has independently come up with an idea for something he too calls Globish. It would use phonetic spellings to create what he considers a neater form of English. This could become a global language enabling links between people from different cultures. Meanwhile Joachim Grzega, a German linguist, is promoting Basic Global English, which has a mere twenty grammatical rules and a vocabulary comprising 750 words that learners are expected to supplement with an additional 250 words relevant to their individual needs.

Although these schemes may be intended in a different spirit, promoting a neutral form of English rather than one freighted with "Anglo" values, they are part of a larger, often invisible project: to establish a community, without territorial boundaries, of people who use English; to make its use seem not just normal, but also prestigious; and to market it as a language of riches, opportunity, scholarship, democracy and moral right. This is supported economically, politically, in education and the media, and sometimes also by military force. Much of the endorsement happens covertly. And as English continues to spread, it seems like a steamroller, squashing whatever gets in its way. True, it is often used alongside local languages and does not instantly replace them. Yet its presence shifts the cultural emphases in the lives of those who adopt it, altering their aspirations and expectations. English seems, increasingly, to be a second first language. It is possible to imagine it merely coexisting with other languages, but easy to see that coexistence turning into transcendence. As English impinges on the spaces occupied by other languages, so linguists are increasingly finding that they need to behave like environmentalists: instead of being scholars they have to become activists.

There have been attempts to create an artificial language for use by all the world. In the second half of the nineteenth century and then especially in the early years of the twentieth, schemes to construct new languages were numerous. Most of these are now forgotten: who remembers Cosmoglossa, Spokil, Mundolingue, Veltparl, Interlingua, Romanizat, Adjuvilo or Molog? Some of the innovators sound like remarkably odd people. Joseph Schipfer, developer of Communicationssprache, was also known for promoting means of preventing people from being buried alive. Etienne-Paulin Gagne, who devised Monopanglosse, proposed that in time of famine Algerians help their families and friends by exchanging their lives or at least some of their limbs for food, and was willing if necessary to give up his own body to the needy.

Only two schemes enjoyed success. In 1879 a Bavarian pastor, Johann Martin Schleyer, devised Volapük. It was briefly very popular: within ten years of its invention, there were 283 societies to promote it, and guides to Volapük were available in twenty-five other languages. As Arika Okrent observes in her book “In the Land of Invented Languages,” Volapük is a gift to people with a puerile sense of humour: ‘to speak’ is pükön, and ‘to succeed’ is plöpön. More famous and less daft-sounding were the efforts of Ludwik Zamenhof, a Polish ophthalmologist of Lithuanian Jewish descent, who in the 1870s began work on creating Esperanto, a language without irregularities. He published his first book on the subject in 1887, summing up the language’s grammar in sixteen rules and providing a basic vocabulary. Zamenhof’s motives were clear; he had grown up in the ghettos of Bialystok and Warsaw, and, struck by the divisiveness of national languages, he dreamt of uniting humanity. Esperanto is certainly the most successful of modern invented languages, but although it still has enthusiastic supporters there is no prospect of its catching on as Zamenhof once hoped.

You are more likely to have heard Klingon, which was originated by Marc Okrand for the “Star Trek” films, and the Elvish languages – notably Quenya and Sindarin, modelled on Finnish and Welsh respectively – devised by J.R.R. Tolkien and faithfully used in Peter Jackson’s films of “The Lord of the Rings.” A more recent example of a new artificial language is the one conceived by Paul Frommer that is spoken by the blue-skinned Na’vi in James Cameron’s 2009 film “Avatar.” Where once they embodied political hopefulness in the real world, invented languages have become accessories of art and entertainment.

Today it is English, rather than any created alternative, that is the world’s auxiliary tongue. There are more people who use English as a second language than there are native speakers. Estimates of the numbers vary, but even the most guarded view is that English has 500 million second-language speakers. Far more of the world’s citizens are eagerly jumping on board than trying to resist its progress. In some cases the devotion appears religious and can involve what to outsiders looks a lot like self-mortification. According to Mark Abley, some rich Koreans pay for their children to have an operation that lengthens the tongue because it helps them speak English convincingly. The suggestion is that it enables them to produce r and l sounds, although the evidence of the many proficient English-speakers among Korean immigrants in America and Britain makes one wonder whether the procedure is either necessary or useful. Still, it is a powerful example of the lengths people will go to in order to learn English, seduced by the belief that linguistic capital equals economic capital.

In places where English is used as a second language, its users often perceive it as free from the limitations of their native languages. They associate it with power and social status, and see it as a supple and sensuous medium for self-expression. It symbolizes choice and liberty. But while many of those who do not have a grasp of the language aspire to learn it, there are many others who perceive it as an instrument of oppression, associated not only with imperialism but also with the predations of capitalism and Christianity. (It is mainly thanks to Lenin’s 1917 pamphlet about imperialism and capitalism that the two words have come to be pretty much synonymous.) The Australian scholar Alastair Pennycook neatly sums up English’s paradoxical status as ‘a language of threat, desire, destruction and opportunity’. Its spread can be seen as a homogenizing (some would say, Americanizing) force, eroding the integrity of other cultures. Yet it is striking that the language is appropriated locally in quite distinct ways. Some times it is used against the very powers and ideologies it is alleged to represent. Listening to Somali or Indonesian rappers, for instance, it seems sloppy to say that the use of English in their lyrics is a craven homage to the commercial and cultural might of America.

In his book “Globish” (2010), Robert McCrum diagnoses English’s "subversive capacity to run with the hare and hunt with the hounds, to articulate the ideas of both government and opposition, to be the language of ordinary people as well as the language of power and authority, rock’n’roll and royal decree." He considers it "contagious, adaptable, populist," and identifies the fall of the Berlin Wall in 1989 as the symbolic moment that signalled the beginning of "a new dynamic in the flow of information." McCrum sees English as performing a central role in what Thomas L. Friedman has catchily called "the flattening of the world," the new "single global network."

There are challenges to the position of English as the dominant world language in the twenty-first century. The main ones seem likely to come from Spanish and Mandarin Chinese. Both have more first-language users than English. But at present neither is much used as a lingua franca. The majority of speakers of Mandarin Chinese live in one country, and, excepting Spain, most Spanish-speakers are in the Americas. There is an argument that the revitalization of minority languages is good for English, because it weakens English’s large rivals and thus removes obstacles to the language’s spread. So, for instance, the resurgence of Catalan, Basque and Galician weakens Castilian Spanish, making it a less powerful rival to English. Apologists for English invert this argument, claiming that the advance of English is good for minority languages. The inversion is spurious.

Nicholas Ostler, a linguist whose insights are often brilliantly surprising, observes that "If we compare English to the other languages that have achieved world status, the most similar – as languages – are Chinese and Malay." All three have subject-verb-object word order, and their nouns and verbs display few inflections. Moreover, "the peculiarly conservative, and hence increasingly anti-phonetic, system is another facet of English that bears a resemblance to Chinese," and "as has happened with Chinese ... the life of English as it is spoken has become only loosely attached to the written traditions of the language." It’s an intriguing link, but hardly a guide to what will happen next.

The main challenges to English may come from within. There is a long history of people using the language for anti-English ends – of creative artists and political figures asserting in English their distance from Englishness or Britishness or American-ness. For instance, many writers whose first language has not been English have infused their English writing with foreign flavours; this has enabled them to parade their heritage while working in a medium that has made it possible for them to reach a wide audience.

Two challenges stand out. I have mentioned India already; English is important to its global ambitions. The language’s roots there are colonial, but English connects Indians less to the past than to the future. Already the language is used by more people in India than in any other country, the United States included. Meanwhile in China the number of students learning the language is increasing rapidly. The entrepreneur Li Yang has developed Crazy English, an unorthodox teaching method. It involves a lot of shouting. This, Li explains, is the way for Chinese to activate their "international muscles." His agenda is patriotic. Kingsley Bolton, head of the English department at the City University of Hong Kong, calls this "huckster nationalism." It certainly has a flamboyant quality; one of Li’s slogans is "Conquer English to Make China Strong." A few dissenting voices suggest that he is encouraging racism, but the enthusiasm for his populist approach is in no doubt, and it is a symptom of China’s English Fever: the ardent conviction that learning English is the essential skill for surviving in the modern world.

The embrace of English in the world’s two most populous countries means that the language is changing. Some of the changes are likely to prove disconcerting for its native speakers. The "English-ness" of English is being diluted. So, more surprisingly, is its American flavour. English’s centre of gravity is moving; in fact, in the twenty-first century the language has many centres. As this continues, native English-speakers may find themselves at a disadvantage. Native speakers freight their use of the language with all manner of cultural baggage. An obvious example is the way we use sporting metaphors. If I say to a Slovakian associate, "you hit that for six," she probably won’t have a clue what I am on about. Nor will an American. An Indian very likely will (the image is from cricket), but really I should choose my words with greater care. The trouble is, often I and many others like me do not exercise much care at all. To non-native speakers, quirks and elaborations of this kind are confusing. Non-native speakers of English often comment that they find conversing with one another easier than sharing talk with native speakers. Already many people who learn English do so with little or no intention of conversing with its native users. If I join their conversations, my involvement may prove unwelcome.

At the same time, native speakers of English tend to assume that their ability in this potent language makes it unimportant to learn other languages. The reality is different. British companies often miss out on export opportunities because of a lack of relevant language skills. Moreover, there is a chance that a command of English will within twenty or thirty years be regarded as a basic skill for business, and native speakers of the language will no longer enjoy any competitive advantage. When polled in 2005, more than 80 per cent of people in the Netherlands, Denmark and Sweden claimed to be able to speak English. The figure was around 60 per cent in Finland, 50 per cent in Germany, 30 per cent in France and Italy, and 20 per cent in Spain and Turkey. These figures can safely be assumed to have increased. They come from a study published in 2006 by the British Council, an organization set up in 1934 and today operating as an "international cultural relations body" in more than a hundred countries. In 1989 its Director General, Sir Richard Francis, stated that "Britain’s real black gold is not North Sea oil, but the English language." That view is often played down, but the role of the British Council in promoting British English ties in with British corporate interests. Large companies such as British Petroleum (now BP Amoco) have worked with the British Council, funding educational schemes to encourage foreign nationals to learn English. This is not exactly an act of altruism. As Robert Phillipson punchily says, "English for business is business for English." But while English is being pushed, it is also being pulled; it is the language, more than any other, that people want to learn.

The consequences are complex. Some, it would seem, are not as intended. Even as vast amounts are spent on spreading British English, the reality is that English is taking on more and more local colour in the different places where it is used. Accordingly, while the number of languages in the world is diminishing, the number of Englishes is increasing.

Henry Hitchings was born in 1974. He is the author of "The Secret Life of Words," "Who's Afraid of Jane Austen?" and "Defining the World." He has contributed to many newspapers and magazines and is the theater critic for the London Evening Standard.