The flag of Iceland was officially described in Law No. 34, set out on 17 June 1944, the day Iceland became a republic. The law is entitled "The Law of the National Flag of Icelanders and the State Arms" and describes the Icelandic flag as follows:
The national civil flag of Icelanders is blue as the sky with a snow-white cross, and a fiery-red cross inside the white cross. The arms of the cross extend to the edge of the flag, and their combined width is 2/9, but the red cross 1/9 of the combined width of the flag. The blue areas are right-angled rectangles, the rectilinear surfaces are parallel and the outer rectilinear surfaces as wide as them, but twice the length. The dimensions between the width and length are 18:25.
The civil flag of Iceland had been used as an unofficial symbol since 1913. It was officially adopted on 19 June 1915, to represent Iceland, and has been in use at sea since 1 December 1918, when Iceland became a separate Kingdom in union with the Danish Kingdom. On 17 June 1944, it was instated as the emblem of the independent republic of Iceland. Like other Scandinavian crosses, it is based on the Dannebrog. The Scandinavian cross shows that Iceland belongs to the family of Scandinavian countries. Other symbolic meanings refer to the natural features of Iceland itself. Blue is the color of the Icelandic mountains, white represents the snow and ice covering the Island for most of the year, and red the volcanoes on the Island.