Crosses in heraldry Crowns. Several national flags are based on late medieval war flags, including the white-on-red crosses of the flag of Denmark and the flag of Switzerland. The elongated Nordic cross originates in the 18th century due to the rectangular shape of maritime flags. The Red Cross flag originates in 1906 as a colour-switched version of the flag of Switzerland. Crosses in heraldry The cross is a basic design of two intersecting lines (X) used from pre-historic times. Its use was enormously expanded as the Christian cross, from about the 6th century, deriving from a T-shape representing the gibbet ("stauros", "crux") of
Flag of Sarawak originally made up of a cross, half blue and half red, on yellow, thought to be based on Brooke's coat of arms. There is a controversy on whether the first flag was made up of "purple" and red, or "blue" and red. On 7 May 1870, the colour of the half blue cross was changed to black by the second Rajah, Charles Brooke, and was hoisted on 26 September, the birthday of the then Rajah Muda Charles Vyner Brooke. It was retained as a coat-of-arms on a Blue Ensign when Sarawak was ceded to the British Crown on 1 July