1927 - September 18 – The Columbia Phonographic Broadcasting System (later known as CBS) is formed and goes on the air with 47 radio stations.

The formation of the Columbia Phonographic Broadcasting System (CBS) in 1927 was a significant event in the history of broadcasting in the United States. CBS was created through the consolidation of various radio stations and networks, including the United Independent Broadcasters and the Columbia Phonograph Broadcasting System.

At its inception, CBS had 47 radio stations under its network, making it one of the largest broadcasting networks in the country at that time. The network quickly grew in popularity, thanks to its innovative programming and talented personalities. CBS became known for its high-quality news coverage, entertainment programs, and sports broadcasts.