Flag of Switzerland to the "Arma Christi" that were especially venerated in the three forest cantons, and which they were allegedly allowed to display on the formerly uniformly red battle flag from 1289 by king Rudolph I of Habsburg at the occasion of a campaign to Besançon. Use of a white cross as a mark of identification of the combined troops of the Old Swiss Confederacy is first attested in the Battle of Laupen (1339), where it was sewn on combatants' clothing as two stripes of textile, contrasting with the red St. George's cross of Habsburg Austria, and with the St. Andrew's cross
Flag of Switzerland squares until 1889, when its dimensions were officially set. The civil and state ensign of Switzerland, used by Swiss ships, boats and non-governmental bodies, is rectangular in shape and has the more common proportions of 3:2. The Swiss flag is one of only two square sovereign-state flags, the other being the flag of Vatican City. The emblem of the Red Cross is the Swiss flag with switched colours. According to the 2017 flag law (SR 232.21), "The Swiss flag shows a Swiss cross on a square background". Special provisions are made for the naval ensign and for civil aircraft identification.