For centuries, the good citizens of Siena peddled the myth that their city was founded by Senius and Ascius, the sons of Remus, twin brother of Romulus (the legendary founder of Rome). Hence the prevalence throughout Siena of the image of the she-wolf (lupa) suckling twins.
The story goes that, when fleeing Rome after their father’s fratricidal murder, one brother rode a white horse, the other a black one, which gave rise to the Balzana, Siena's coat of arms. The Balzana takes the form of two horizontal bands, the upper white the lower black, symbolising the triumph of good over evil.
Needless to say, Siena's enemies had a rather different take; the white band signifies how the Sienese talk and the black how they think.