The strange symbolism of Gdansk's flags is both remarkable and unique. During the 1930s, especially after the rise of National Socialism, the city authorities introduced flags with a distinctly Germanic design, as can be seen in the flags of the police and the Heimwehr, the SS militia that operated in the city and surrounding countryside of the Free State. These flags feature clear Nazi symbols such as the swastika and the Totenkopf. In contrast, a double flag, combining the colors of Gdansk with a white half bearing the Polish coat of arms, had been in circulation since 1920 (probably 1922) in the port area.