The Atlanta Falcons named Dan Quinn as their new head coach and signed the former Seattle Seahawks defensive coordinator to a five-year contract Monday. Over the last two years, Quinn guided arguably the best defense the league has seen since the 2000 Super Bowl champion Baltimore Ravens, with Seattle leading the league in total defense and points allowed in consecutive seasons.

But if history holds true, it isn’t fair to assume that Quinn’s success as the Seahawks defensive mastermind will translate into a title for the Falcons.

Among the two most storied and winning defenses in NFL history were the 1985 Chicago Bears, helmed by Buddy Ryan, and the Ravens led by Marvin Lewis. Both teams would win Super Bowls, and both remained competitive in the years that followed.

But after Ryan and Lewis moved on to become head coaches, they didn’t or haven’t achieved the same level of success.

Ryan, capitalizing on his work with Chicago, became the Philadelphia Eagles head coach the following year and went 5-10 in his first season. The Eagles would improve each year under Ryan, going 7-8 in his second season, then 10-6, 11-5, and 10-6 over the next three years.

The Eagles would make the postseason in each of the last three years under Ryan, but their defense would never come close to equaling the ’85 Bears. From 1987 to 1989, Philadelphia was either No. 1 or No. 2 in turnovers forced, and in 1990 owned the NFL’s best rushing defense.

But the Eagles were ousted from the postseason in the first round three straight times under Ryan, and while he’s still revered in Philadelphia, Ryan was never able to recreate the same magic he had with Chicago.

Ryan, now 80, had one more go round as a head coach with the Arizona Cardinals, going 12-20 overall and never making the postseason.

Then there’s Lewis, who eventually left the Ravens to join the Cincinnati Bengals in 2003. The 56-year-old is now one of the longest tenured head coaches in the NFL, an amazing feat on its own, but he’s yet to win a playoff game in 12 seasons.

The Bengals have a 100-90 overall record under Lewis, and have only three losing seasons during his run. But in six postseason appearances, the Bengals have lost in the first round every time.

Much like Ryan, Lewis was able to morph the Bengals into a turnover machine, ranking as high as third twice and first in the 2005 season. It wasn’t until 2013 that the Bengals ranked No. 3 in total defense.

The success of Ryan and Lewis had a great deal to do with their personnel. The Bears featured future Hall of Famers like defensive end Richard Dent and middle linebacker Mike Singletary, to say nothing of former all-time rusher Walter Payton killing the clock with his sweeping runs.

The Ravens boasted Hall of Fame defensive back Rod Woodson and soon-to-be-inducted linebacker Ray Lewis, along with Pro Bowlers Peter Boulware and Michael McCrary. To this day, Lewis is one of only nine defensive players to win Super Bowl MVP.

During his short two-year window with the Seahawks, Quinn’s had the opportunity to coach some of the league’s premier defensive stars. For starters, there’s the three-headed defensive back monster of Richard Sherman, Earl Thomas, and Kam Chancellor, a group that’s made a combined six All-Pro first-teams and nine Pro Bowls.

Quinn also got to work with top pass rushers like defensive end Michael Bennett, and linebackers Bruce Irvin and Bobby Wagner. Cliff Avril and K.J. Wright have also been solid contributors.

After their poor team defense in 2014, the Falcons undoubtedly believe Quinn’s expertise can lift them atop the NFC. And they’re likely aware that personnel will have much to do with his success, since they gave him power to help construct the roster, according to ESPN.

Quinn was able to earn the job over other leading contenders, like Detroit Lions defensive coordinator Teryl Austin. Falcons management also reportedly had an interest in Adam Gase, the offensive coordinator of the Denver Broncos. But the Falcons knew they had to bolster their defense, and Quinn owned the experience and success needed to turn around a struggling unit.

Atlanta finished dead last in the NFL in total defense, letting up 398.3 total yards and 279.9 passing yards per game. The team also owned the second-worst pass rush in the league with 22.0 total sacks. It's no wonder they finished the season with a 6-10 record in arguably the worst division in the NFL.

But Atlanta will enter next season with plenty of returning talent, especially in the secondary. The Falcons were tied for sixth in the NFL with 28 turnovers forced, the majority of which came from the interceptions by strong safety Kemal Ishmael and cornerbacks Desmond Trufant and Robert Alford.

Quinn likely knows the history of top defensive coordinators trying to make the transition to head coach, and with the likes of Ishmael, Trufant and Alford already on the roster, he could fill holes with some new talent from the draft to reverse some of the problems of 2014. 

"All sorts of challenges ahead, lots of hard work to do. But I can't wait to get started," Quinn said at his press conference.