Originating from WGN Radio's studios at the Tribune Tower's Centennial Building annex in the Magnificent Mile district, the inaugural broadcast included dedicatory speeches from McCormick, Chicago Mayor Martin Kennelly, U.S. with a two-hour-long special, WGN-TV Salute to Chicago. Regular programming commenced on April 5, 1948, at 7:45 p.m. WGN-TV began test broadcasts on February 1, 1948, then informally signed on the air on March 6 to broadcast the 1948 Golden Gloves boxing finals from the Chicago Stadium. The front page of Part Five of the Chicago Sunday Tribune of April 4, 1948, announcing the launch of WGN-TV the next day. The three-letter base call sign served as an initialism for 'World's Greatest Newspaper', a tagline and slogan used by the Tribune since 1909.

By January 1948, however, the company decided to call its new television property WGN-TV after WGN, which had been owned by the Tribune since 1924. After the FCC awarded the permit on November 8, the group originally requested to assign WGNA as the station's call sign. McCormick and the owner of WGN and WGNB submitted an application to the Federal Communications Commission (FCC) on September 13, 1946, and under the 'WGN Incorporated' subsidiary, to build a television station on VHF channel 9. The Chicago Tribune Company, headed by Chicago Tribune editor and publisher Robert R. WGN-TV, WGN radio and the now-defunct regional cable news channel Chicagoland Television (CLTV) were the three flagship properties of Tribune Broadcasting, itself part of the Tribune Media conglomerate (formerly known as the Tribune Company until August 2014), until the company's purchase by Nexstar was completed in September 2019. A charter affiliate of both The WB and of successor network The CW, WGN-TV reverted to being an independent station in 2016. Later renamed WGN America, the former superstation feed was converted into a conventional basic cable network in December 2014, enabling it to be added to local cable providers, and later soft re-launched as NewsNation in September 2020. television station to be made available via satellite transmission to cable and direct-broadcast satellite subscribers nationwide. Like concept progenitor WTBS in Atlanta, WGN-TV was a pioneering superstation on November 8, 1978, it became the second U.S.

Its transmitter is located atop the Willis Tower in the Loop. WGN-TV's studios are located on West Bradley Place in Chicago's North Center community as such, it is the only major commercial television station in Chicago which bases its main studio outside the Loop. Owned by Nexstar Media Group, it is sister to the company's sole radio property, news/talk/ sports station WGN (720 AM). WGN-TV (channel 9) is an independent television station in Chicago, Illinois, United States.

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