The late-night legend took aim at his former network home and David Ellison's media company, speculating that Colbert's show was canceled for political reasons.

David Letterman delivered a fiery rant against CBS and parent company Paramount for cancelling Stephen Colbert’s “Late Show,” calling the decision “gutless” and “pure cowardice” as he labeled his successor a martyr of the network.

David Letterman unloaded on CBS and Skydance on Friday for cancelling “The Late Show,” which he launched 32 years ago, saying the network had mistreated his successor, Stephen Colbert. In an interview posted to his YouTube channel,