Which European country's flag features a white cross on a red background?

Switzerland’s flag features a white Greek cross on a red background. Unlike most national flags, it is square, giving the Swiss design an especially distinctive appearance.

The white cross began as a military identification mark used by soldiers of the Old Swiss Confederacy. It is first clearly recorded at the Battle of Laupen in 1339, when Swiss combatants wore white textile crosses to distinguish themselves from opposing forces. Over time, the symbol became associated with the Confederacy itself.

The modern flag was adopted in the nineteenth century, with the square red-and-white design taking shape in 1840–41. Its dimensions were formally specified in 1889, and Swiss law later defined the cross’s proportions more precisely. The flag’s square form reflects medieval and early-modern military banners rather than the rectangular maritime tradition common elsewhere.

Denmark can be confused with Switzerland because both use a white cross and red field. Denmark’s cross is a Nordic cross extending to the flag’s edges, while Switzerland’s is centred and free-standing. The Red Cross reverses the colours: a red cross on white.