The phoenix is a mythological bird that is reborn in flames, rising from its ashes after it dies.
Many people believe that the phoenix's appearance on the flag is a reference to the 1906 San Francisco earthquake and fires. In fact, the flag predates the disaster, but is instead a reference to several other disastrous fires in the city's history, including six between the years 1849 and 1852.
Blazon, or formal description Edit
The blazon below is an attempt at generalizing the flag pictured here into a vexillological description of the design:
Argent bordered Or a phoenix Tenné rising from the flames Proper above a scroll Argent bordered Sable with the motto "Oro En Paz Fierro En Guerra" in Or, beneath it the words "San Francisco" in Azure.
About the designEdit
The flag design violates at least two principles of vexillology (the science of flag design), both traditionally established in vexillological practice, and explained in various modern publications, including those by North American Vexillological Association (NAVA).
The San Francisco flag contains the words "San Francisco", as well as the city motto. A flag design should not use any lettering. Words can be hard or impossible to read from a distance, not to mention the difficulty in making them out when the flag is flying on the wind.
On top of that, the letters of the motto are gold (yellow) on a white background. This color combination is a violation of heraldic rules, and results in a low-contrast pairing, which is extremely difficult to read.
It has also been suggested that the gold (yellow) border around the flag was initially a fringe of gold tassels surrounding a white flag, and then later incorporated into the flag design, possibly by mistake.
The design was ranked #35 out of 150 in a 2004 US city flags survey done by NAVA.