By the turn of the century, the city that barely existed in the 1830s and was ravaged by the Great Fire of '71 had become known as that most American of cities.

Chicago was a place of great contrasts.

Quintessentially American, more than three-quarters of its residents were of foreign parentage. Home to lush parks and tree-lined boulevards, its streets were littered with uncollected horse manure. Temperance capital, Chicago had a tavern for every 200 residents.

Home of empire builders, it was also the center of the nation's trade union and anarchist movements the and site of violent labor clashes. At the same time, it was laying claim to the title "Hog Butcher for the World," it was establishing world-class cultural institutions.

With the dawn of the 20th century came a stunning engineering achievement - the reversal of the Chicago River, laden with waste from the stockyards, which helped the city to shed its grim distinction as cholera capital of the world.

Chicago began to wear the mantle of corruption in earnest with the election of William Hale "Big Bill" Thompson as mayor in 1915, and - not coincidentally - the arrival of Al Capone from New York a few years later.

As the Great Depression took hold, it exacted an enormous toll on Chicagoans, leaving 750,000 residents unemployed and civil servants and teachers working without pay.

As Chicagoans did their patriotic best during the war years, another event occurred that will long reverberate: In 1942, the city became the site of the world's first controlled atomic reaction.

The end of the war brought unprecedented suburban growth. By 1950, the city's population was 3,621,000; the suburbs had about 2 million residents.

The 1950s also introduced two Chicago giants: O'Hare International Airport and Mayor Richard J. Daley.

The city also was granted the ignominy of being named the nation's most segregated city by Edwin Berry of the Chicago Urban League.

Daley gained national headlines in 1960 when John F. Kennedy defeated Richard Nixon in the presidential election, amid charges that vote fraud in Chicago put him over the top.

Turmoil closed the decade. In April 1968, riots erupted and West Side houses and stores were burned after the assassination of the Rev. Dr. Martin Luther King Jr., causing Daley to issue his infamous "shoot-to-kill" order. That August, the Democratic National Convention was marked by bloody clashes between police and anti-war demonstrators.

The '70s brought the construction of the then-world's tallest building, the 110-story Sears Tower. It also brought Daley's death.

Another Bridgeport resident, Michael Bilandic, took over as mayor. But he did himself and the Chicago Machine irreparable damage when he disingenuously maintained all was well when a record snowstorm buried the city in 1979.

Bilandic's blunder gave way to the election of the city's first female mayor, Jane Byrne. her legacy included the Taste of Chicago and civic improvements that flower today.

The first female mayor was followed by the first black mayor, when Harold Washington took office in 1983. He gave hope to black residents whose power never equaled their numbers.

The charismatic Washington clashed repeatedly with a city council majority bloc of aldermen led by Edward Vrdolyak and Edward Burke.

Washington's supporters were left reeling from his death in 1987, which paved the way for another Daley, Richard M., to take office.

Daley wasted little time making his mark. He forged racial coalitions, set out to make the city greener and prettier, and took control of the troubled Chicago public schools and public housing sectors.

Daley is, of course, not without his detractors. He has inspired criticism, for example, when friends and campaign contributors wound up with huge city contracts.

That aside, the city appears well positioned to enter the new millennium. It shows no signs of relinquishing its economic prominence in the metropolitan region.

Downtown is being revitalized, with continued efforts to turn it into a high-tech haven; construction of the 25-acre Millennium Park; and an influx of residents turning it into not only a place to work and play, but live.

Chicago is increasing becoming an intellectual locus. That's good news as we enter the millennium and make the shift toward a digital economy, said Joseph Bast, executive director of the Heartland Institute, a not-for-profit research organization.

Chicago's quality of life will become the central issue as people become even more mobile, he said.

"As important as that was 50 years ago, it's much more important now as we compete to pull (tourists and residents) here," he said.

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