The cyan and white bars represent geographical features of the city: the cyan stripes for Lake Michigan and the North Branch of the Chicago River; the top, middle, and bottom white bars for the North, West, and South Sides, respectively.
The four red, six-pointed stars symbolize four of the most historically significant events in the city's history. The first is for the U.S. Army's Fort Dearborn and the massacre of settlers and destruction that took place there in 1812 at the hands of local Native Americans. The second is for the Great Chicago Fire of 1871, which wreaked havoc on the city, destroying a large portion of its buildings and infrastructure. The third represents the World's Columbian Exposition of 1893, a truly international event and a major milestone in establishing Chicago as a world-class city. (The 2003 best-seller The Devil in the White City by Erik Larson details this extraordinary event.) And the fourth star represents the Century of Progress Exposition of 1933-34, which commemorated Chicago's first one hundred years of existence and further bolstered the effects of the Columbian Exposition forty years earlier. It was speculated that if Chicago had won its bid to host the 2016 Summer Olympics (instead of Rio de Janeiro, Brazil), that event would have been a prime candidate for a fifth star on the flag.
Each star's six points represents a unique value, attribute, or historical fact about the city. The first star's points represent transportation, labor, commerce, finance, populousness, and salubrity (a fancy way of saying healthiness). For the second star, the values of religion, education, aesthetics, justice, beneficence, and civic pride are symbolized. The points of the third star stand for the six governments that the territory of Illinois (and what eventually became Chicago) has been ruled by: France (1693), Great Britain (1763), Virginia (1778), Northwest Territory (1798), Indian Territory (1802), and the State of Illinois (1818). The last star's points stand for various mottos, nicknames, and other concepts relating to Chicago: its status as the United States' third largest city; the City seal's Latin motto Urbs in Horto ("City in a Garden"); the motto "I will"; Chicago as "Great Central Market" to the nation; "Wonder City" in reference to its rapid growth and national economic importance, especially at the turn of the 20th century; and its firmly established reputation as the "Convention City," where businessmen and women from around the nation and the globe often meet.
Chicago's municipal flag is extremely popular among the city's inhabitants. The cyan bars and red stars can be seen in the form of tattoos, t-shirts, accessories, and beyond, in addition to various sizes of flags. In fact, the design is so beloved that in a survey conducted by the North American Vexillological Association in 2004, it was voted the second most popular American city flag; the number one spot went to Washington, D.C.
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