The flag of Zürich is derived from a blue-and-white design attested since the 1220s, the diagonal division of the flag is first attested 1389.
The flag of Zürich was adorned by a red Schwenkel since 1273. This was regarded as a mark of sovereignty and honour by the people of Zürich, but the Schwenkel was otherwise used as a mark of "shame", identifying replacement flags used after a real flag was captured by an enemy This led to a misunderstanding after the Battle of Nancy, when the Duke of Lorraine removed the Schwenkel from the Zürich flag, stating that with the present victory, Zürich had "erased its shame". The perplexed Zürich troops later quietly re-attached the 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).
Most mass-produced flags are commonly 150x90cm / 5x3' or 90x60cm / 3x2', which will often vary from the official size ratio. We now offer a custom-manufactured official size option for our many of our flags.