The personification of Liberty is often associated with a loose, pointed cap, named after the ancient Phrygians, who wore it to distinguish free men from slaves. Citizens of ancient Rome later adopted the cap, and its symbolism was revived during the American Revolution as a common emblem of freedom. Following the War of 1812, the Goddess of Liberty became a popular symbol in the United States and was often shown holding the cap aloft on a pike. By mid-century she began to appear, as here, on weather vanes, wearing the cap and pointing into the wind with her outstretched arm.
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