“Coffee and kleina,” reads a large sign at a roadside coffee shop by one of the main roads in Reykjavik. Not so many years ago, such a billboard would simply have read: “Kaffi og kleina” – in the language of the Vikings, the official language of Iceland.

It is a privilege of the few to be able to read and write Icelandic, a language understood by only around 400,000 people worldwide. Icelandic, in which the historic Sagas were written in the 13th and 14th centuries, has changed so little since then on our small and isolated island, that we can still more or less read them as they were first written.

But Iceland is not so isolated anymore, and there are signs its language is facing challenges never seen before. Following the economic crash of 2008, and the subsequent collapse of the Icelandic currency (making Iceland a much cheaper destination than before), tourism has emerged as the largest industry in Iceland, with 2.5 million tourists expected to visit a country of 350,000 people this year alone.

And everyone is catering to the tourists in English, of course. At restaurants and coffee shops, people are frequently greeted in English rather than Icelandic, and often Icelandic will get you nowhere if you want to order food or drink. Companies use English names or are rebranding themselves in English. The importance of tourists to the economy is rapidly making English not only a second language in the service industry, but almost the first language. (The irony of this article being written in English is certainly not lost on me.)

There are other warning signs. Icelanders have always been very proud of their literary heritage, boasting that we write and read a lot of books. However, Icelanders bought 47% fewer books in 2017 than they did in 2010, a very sharp decrease in a matter of only six years. In a recent poll in Iceland, 13.5% of those who responded had not read a single book in 2017, compared to 7% in 2010.

Will Icelandic soon become the second language of Icelanders?

Iceland has a wonderful tradition of giving books as Christmas presents, with people reading into the night on Christmas Eve. However, even this may be under threat: in 2005, an Icelander received an average of 1.4 books as gifts at Christmas; this number is now 1.1, with 42% of Icelanders not receiving a single book for Christmas according to the most recent poll.

And we must consider the effect on our youngest generation. In Iceland, foreign films or TV shows have always been shown with subtitles, rather than being dubbed, resulting in most Icelanders being able to speak English. While Icelandic broadcasters have always dubbed cartoons and children’s shows, the online world has no borders. Kids today have almost an unlimited access to entertainment in English – movies and TV series on streaming services, video games, YouTube. Recent research shows an alarming rise in students under 15 struggling to read their own language. And they are picking up English at a much faster pace than before – it is not strange to hear them speaking it in the playground.

Will Icelandic soon become the second language of Icelanders? All languages evolve, but so far we have managed to help Icelandic adapt to technological changes by creating new words for modern inventions such as the telephone (sími), TV (sjónvarp), email (tölvupóstur) and computer (tölva). Further evolution is, of course, inevitable. But with the ubiquity of English, is the Icelandic language at risk of disappearing more or less completely, and sooner rather than later?

And this, of course, leads to the question: what value does a language have? If it is in danger, should we make an effort to save it?

In my mind, the answer is clear. Not only should we make an effort, but it is almost our moral obligation. First and foremost, we need to keep reading and writing in Icelandic. There are various efforts that can and have been made on that front. The government (led by a prime minister who holds a degree in Icelandic literature, and happens to be a leading expert on its crime fiction), has recently proposed that the state should reimburse 25% of the costs of publishing books in Icelandic. This legislative proposal could turn things around.

On a smaller scale, but with similar objectives in mind, myself and fellow crime writer Yrsa Sigurðardóttir set up a debut author award last year in Iceland. The Svartfuglinn (Blackbird) prize is for new crime fiction in Icelandic, in order to encourage emerging authors to keep writing in the language. In a similar spirit, Iceland’s leading producer of audiobooks has announced a goal to publish one new audiobook per day in Icelandic.

But there is another sign of salvation on the horizon, from an unlikely source. Icelandic rap has been growing in popularity in recent years, and the leading artists in that genre usually write their lyrics in Icelandic, rather than English. Looking at the top songs in Iceland on Spotify, there are four Icelandic rap songs in the Top 5 – all performed in Icelandic. So, perhaps there is still hope.

• The Darkness by Ragnar Jónasson is published by Penguin.