The Union Stock Yard & Transit Co., or The Yards, was the meatpacking district in Chicago for more than a century, starting in 1865. The district was operated by a group of railroad companies that acquired marshland and turned it into a centralized processing area. By the 1890s, the railroad capital behind the Union Stockyards was Vanderbilt money. The Union Stockyards operated in the New City community area for 106 years, helping Chicago become known as the "hog butcher for the world," the center of the American meatpacking industry for decades. The yards became inspiration for literature and social reform.
The stockyards became the focal point of the rise of some of the earliest international companies. These refined industrial innovations and influenced financial markets. Both the rise and fall of the district reflect the evolution of transportation services and technology in America. The stockyards have become an integral part of the popular culture of Chicago's history. They are considered one of the chief drivers that empowered the animal–industrial complex into its modern form.
From the Civil War until the 1920s and peaking in 1924, more meat was processed in Chicago than in any other place in the world. Construction began in June 1865 with an opening on Christmas Day in 1865. The Yards closed at midnight on Friday, July 30, 1971, after several decades of decline during the decentralization of the meatpacking industry. The Union Stock Yard Gate was designated a Chicago Landmark on February 24, 1972, and a National Historic Landmark on May 29, 1981.
Before construction of the various private stockyards, tavern owners provided pastures and care for cattle herds waiting to be sold. With the spreading service of railroads, several small stockyards were created in and around the city of Chicago. In 1848, a stockyard called the Bulls Head Market was opened to the public. The Bulls Head Stock Yards were located at Madison Street and Ogden Avenue. In the years that followed, several small stockyards were scattered throughout the city.