Centaurea montana; The perennial cornflower actually is not an Icelandic species. I saw individual plants growing along a creek near Mosfellsbær, near Reykjavik in the mild climate region of Iceland. It probably somehow germinated from seed from a garden plant and settled in a semi-wild habitat. It is closely related to the common annual European cornflower.
It is a member of the daisy family (Compositae).