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.

A little more than a week after Stephen Colbert announced the cancellation of The Late Show, the long-running talk show’s former host, David Letterman, finally broke his silence about the situation. In a video posted on his YouTube account on Friday,