Rivera, previously a defensive coordinator with the San Diego Chargers, replaces John Fox, who was released after the Panthers finished with a league-worst 2-14 record earlier this month.
"I think there was a fit, listening to what they wanted from a coach, their philosophy, which made me feel comfortable," said Rivera. "The timing was really good. This was the first opportunity I really had going into interviews that I wasn't in the playoffs."
Panthers owner Jerry Richardson said he saw the right approach in Rivera's attitude toward building a winner.
"Ron has coached units that have performed at a consistently high level on defense and also understand the importance of having an offense and special teams that complement the defense," said Richardson. "He brings an approach and resume that we believe lends itself to success."
One key issue that Rivera will have to address is the quarterback role, where Jimmy Clausen struggled in his rookie year with three touchdowns and nine interceptions in 13 games.
Rivera suggested that Clausen may have been given the starting role before he was ready but was careful not to be dismissive of the former second-round draft pick.
"Jimmy was forced out there, put into a very tough situation," said Rivera. "Until we get a chance to truly evaluate him from an offensive coordinator and a quarterback coach it would be unfair to talk about him.
(Reporting by Simon Evans; Editing by Frank Pingue)