Flags and arms of cantons of Switzerland Schwenkel. Zürich attached the Swiss cross in the red Schwenkel rather than in the main flag, and this may have contributed to the development of the flag of Switzerland (placing the white cross in a red field by default). The city of Bern is a Zähringer foundation of 1160. In the 13th century, its flag showed a black bear in a white field, changed to the current red-and-yellow diagonal arrangement in 1289. Bern also had a war flag with a simple red-and-black horizontal division. The cantonal colours remain red and black. The blue-and-white flag is attested from 1386. The vertical
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.