It is always said of Icelandic that it is a very conservative language. True. Modern Icelandic is close to its Old Norse roots and has preserved morphological features long lost not only in continental Scandinavian and West Germanic, but also partly in closely related Faroese. /1

Iceland's isolated geographic position is often said to be the main reason. Also true, but it's not the only one. Icelandic looks the way it does also thanks to strictly puristic language policies aimed at limiting the number of loanwords in favour of Icelandic-based neologisms/2

For centuries Iceland was under Danish rule. Although not quite as pervasively as in Faroese, Danish did have an influence on Icelandic. In the 19th century, the independence movement in Iceland also implied a desire to preserve the language as free from Danish as possible. /3

Words and rare declension patterns that had fallen out of use were reintroduced in a very conscious and successful effort to keep Icelandic's unique character intact.

Many of those language policies are still in place today, but no language is frozen in time or isolated. /4

Today English is having a quite pervasive influence on Icelandic, much more so than any other language before.
What this means for the Icelandic language in the long term only time can tell. /5 - The End