This is a very 'Anglo-Saxon' question. There are many nations with languages other than English, e.g Germany, Indonesia, Myanmar, Thailand. The significance given to language as a means of nation-building varies. In Indonesia, the common language helped, in Malaysia and Sri Lanka the attempt to enforce one language split the country and society. In Switzerland, four languages do not prevent being a nation. And as you will be aware, in India, there are at least 28 acknowledged languages, but that does not prevent her being a nation. The question must be considered from case to case individually.

Very interested in the answer!

Nation-Building processes differ in their manifestations. The national identity markers play different roles in different environments.. For Georgian case language as identity marker is very important as Georgian language is characterized with durability through the millennia. For example if one knows modern Georgian he/she can easily understand texts created in the 4th century: it is because Georgian enjoyed uninterpreted developments during many centuries. Georgian language's unique "flexible stability" ensures its pivotal role in making Georgian (ethnic and national) identities. If you will be interested to go in this issue deeply and observe nation-formation process on a base of Georgian case study , you can visit my page on Research Gate.

South Africa, Ireland, Wales, Belgium, Namibia, Kenya and Nigeria all have their own interesting and colourful stories to tell regarding the importance of various language[s] in defining the identity of the country as a whole - or of a specific prominent group within it.

[Dagmar - I do have the impression that language is a very sensitive and divisive issue in India - particularly in Tamil Nadu].

David: You are absolutely right.

Today English is the language of science and this is why it is so important to the people of the world.

There is no doubt one should know English (and possibly French and some other language) to be able to communicate. But that has nothing to do with nation-building or national consciousness. A national language is different from a lingua franca.

Dagmar - Indeed, as you imply, in Belgium, Germany and Scandinavia, English does not really contribute to "nation-building" as such, despite the fact that many people there speak it very well. In South Africa, on the other hand, it is by far the dominant tongue, even though that country's official constitution does not give it any priority over the many others which are used there - [of these, Afrikaans, Zulu and perhaps others are certainly important features of the national character]. Officially, Irish is the main language of Eire, but it is very debatable how much it contributes to the national 'consciousness'. [With Welsh > Wales, however, probably quite a lot]. In Namibia, English is the official language, Afrikaans is the lingua franca (in the cities, at least) - but German still serves to add distinctive 'colour' to the country. And in India, English still fulfils an indispensable role, despite its controversial status.

David: It is a very complex issue (btw. Belgium has two - some say three - national languages: Flemish which resembles Dutch, French and in some pockets German). In Northern Ireland there is a bitter controversy about the compulsory teaching of the Irish language in schools; in the republic the attitude is more relaxed: there the nation is more secure. We have to distinguish between a national and official language: in India, Hindi is the national language, and English an official one. The problem arises mostly when the planned national language is perceived as oppressive or coercive by some, often minority, groups: Hindi by the Tamils in India, Sinhala by the Tamils in Sri Lanka, Bahasa as religiously oppressive by the minorities in Malaysia. All these groups favour English as a sort of 'neutral' way out. In Indonesia, on the other hand, Bahasa is no problem at all because it was consciously chosen as the national language by a broad coalition of groups fighting for independence (Bahasa was incidentally not the language of all groups in Indonesia, it was already a sort of lingua franca).

Sorry for the long answer, to put it short: English, to my mind, has not contributed to nation building as such in any colonised country, unlike in the UK and unlike German in Germany (the German we speak and write is something very different from what existed before: what we call high German was the language of the theatre in Hannover, and Luther wrote his translation of the bible in the language of the 'Saxon chancelleries'). English was at best a way round other confrontations.

Dagmar - Please do not apologise for the length of your answer - which was interesting, as well as being largely true: (I am inclined to question your: "English ... has not contributed to nation building as such in any colonised country").

Incidentally, the Belgians who have moved here to southeast Spain say that they regard themselves primarily as Flemings, rather than Belgians. In 1830, the dividing line with Holland was drawn on the basis of religion, but nowadays linguistic identity is far more important. Apparently the Walloons are not all that keen to perfect their command of Flemish.

In South Africa before 1994, Afrikaans was imposed as the main language of the civil service and the armed forces, but that has been reversed.

David: You are right about the Belgians, here we say that Belgium is held together only by the monarchy and their national football club. But they seem to do very well even in the long phases when they have no functioning government - must be a good administration. What I meant to say, of course, and what you also imply is that language is never language alone, but that all kinds of ethnic, also religious and other identities are tied to it. That makes it conflictual.

Thanks Dagmar … In South Africa, an ever-increasing number of Bantu families are adopting English as their primary [even home] language. And the people in that country of Indian descent, despite retaining their Hindu or Muslim religions, switched to English many, many decades ago.

So they did in Singapore, though there exist officially four national languages. On the other hand, most people in Singapore are at least bi-lingual. Whether a language remains alive also depends on its prestige, and sadly, often the language of the colonial or dominant power had more prestige than the local ones which were often known only as 'vernacular'. Ben Anderson has written about this phenomenon in detail.

Indeed ... At the same time British, French and other colonists in Africa (and elsewhere?) deserve a fair amount of credit for strengthening and preserving many of the indigenous languages - by giving them written form, and then by publishing dictionaries, grammars and story books. By way of contrast, the deliberate destruction of the majority of Mayan manuscripts was a terrible crime. Only very recently, has some progress been made in deciphering the ancient script.

This is where I become patriotic: the first people to catalogue Indian languages (Tamil etc.) and their grammar were German missionaries (17th century). The English came later. And in Myanmar it was an American missionary who devised a script for the Kachin language in the 19th century. But you are right: that was all much better than what happened in Latin America. Were they conquerors more barbaric or was it a more barbaric age? Who knows?