Short answers, pulled from the story.
Chicago is derived from a French rendering of the Miami-Illinois word for a wild relative of onion and garlic called Allium tricoccum. The explorer Henri Joutel noted in his 1688 journal that this garlic grew profusely in the area, and the first known written reference to the site as "Checagou" was made by Robert de La Salle around 1679.
Jean Baptiste Point du Sable, a trader of African descent possibly born in the French colony of Saint-Domingue, established the first known permanent settlement in the area in the 1780s and is commonly called the Founder of Chicago. The Town of Chicago was organized on the 12th of August 1833, and the City of Chicago was officially incorporated on Saturday, the 4th of March 1837.
The Great Chicago Fire on the 8th of October 1871 destroyed an area about 4 miles long and 1 mile wide, killing at least 300 people and leaving more than 100,000 homeless. Much of the industrial infrastructure including railroads and stockyards survived, and the rebuilding period produced the world's first steel-framed skyscraper in 1885.
The St. Valentine's Day Massacre occurred in 1929 when Al Capone sent men to kill members of the rival North Side gang led by Bugs Moran, leaving seven people dead. It took place during the Prohibition era, which in Chicago ran roughly from 1919 to 1933.
On the 2nd of December 1942, physicist Enrico Fermi conducted the world's first controlled nuclear reaction at the University of Chicago as part of the top-secret Manhattan Project. This experiment contributed to the creation of the atomic bomb, which the United States used in World War II in 1945.
Chicago is the birthplace of house music, a form of electronic dance music, and of industrial music. In the 1980s and 1990s, the city was the global center for both genres. Chicago also has deep roots in blues, jazz, gospel, soul, and hip-hop, and is home to the Chicago Symphony Orchestra.