The network is the second-oldest unit of ViacomCBS after Paramount Pictures. CBS Radio traces its roots to CBS's predecessor, United Independent Broadcasters, founded in 1927 with 47 network affiliates. The next year, Columbia Records invested in the radio network, which was named the Columbia Phonographic Broadcasting System. Eventually, the record company pulled its backing from the struggling web. William S. Paley bought a half-interest in what became the Columbia Broadcasting System in 1928, and became its president. (In 1938, CBS bought its former parent, Columbia Records.) For more about the network's history, see CBS.