Epic Debates: Which are the greatest dynasties?

Over the years, North America's "Big Four" leagues - the NFL, NHL, NBA, and MLB - have seen powerhouses reach their respective summits and then knock off challengers for years to come.

When a team accrues enough continued success in an era, it eventually elevates to "dynasty" status, which defines its dominance from a historical perspective.

But the question remains: Which dynasties reign supreme above others? Here's our top 10.

10. Cincinnati Reds

Years of dynasty: 1970-79
Championships won: 2

You know a team is incredible when it's bestowed a nickname like the "Big Red Machine."

To this day, the 1970s Cincinnati Reds are regarded as one of the greatest sides in baseball history. Those Reds won two World Series titles and claimed four National League pennants thanks to a revered lineup known as "The Great Eight" - Johnny Bench, Tony Perez, Joe Morgan, Dave Concepcion, Ken Griffey, Cesar Geronimo, George Foster, and, of course, Pete Rose, MLB's all-time hits leader.

Rose remains permanently ineligible for the Hall of Fame due to his gambling scandal, but that doesn't erase his and the Reds' dominance.

9. Montreal Canadiens

Years of dynasty: 1970-79
Championships won: 6

An injury to starting goaltender Rogie Vachon late in the 1970-71 campaign provided Ken Dryden with an opening to seize the Montreal Canadiens' No. 1 role. After posting an impressive 1.65 goals-against average in six regular-season appearances, Dryden got the call in the playoffs and won the Conn Smythe Trophy for backstopping the Habs to their first Cup of the '70s.

Dryden would remain in goal for the team's remaining five championships that decade, but he was far from the only big-time contributor. Right winger Guy Lafleur recorded at least 119 points in five straight seasons during the Canadiens' dominant run, leading the NHL in scoring on three occasions. Meanwhile, the blue line featured Hall of Famers Guy Lapointe, Serge Savard, and Larry Robinson.

With Scottie Bowman, the league's all-time winningest coach, behind the bench for eight seasons, the Canadiens were loaded from top to bottom.

8. Pittsburgh Steelers

Years of dynasty: 1974-79
Championships won: 4

The hiring of Chuck Noll in January 1969 laid the groundwork for the Pittsburgh Steelers' most prosperous era. The legendary head coach was influential in the club's draft selections of Terry Bradshaw, "Mean" Joe Greene, and Lynn Swann, who would lead Pittsburgh's march through the league during the mid-to-late '70s.

Behind the famed "Steel Curtain" defense, the Steelers became the only NFL team to win four Super Bowls in six years. In Super Bowl IX, Pittsburgh held the Minnesota Vikings to 17 rushing yards and a record-low 119 total yards in a 16-6 victory. A year later, defensive end L.C. Greenwood set a Super Bowl record with four sacks in the Steelers' 21-17 triumph over the Dallas Cowboys in Super Bowl X.

7. New York Islanders

Years of dynasty: 1979-1984
Championships won: 4

The New York Islanders became the second team in NHL history to hoist Lord Stanley in four consecutive seasons. While the Canadiens had completed the same feat immediately prior, New York had to win an extra playoff series in each of their Cup runs. In 1979-80, the NHL's expansion led to a revamped playoff format, which eliminated the first-round bye that had been given to each division winner.

During the Islanders' dominant four-year span, the club was never pushed beyond a Game 6 in any series. New York's "Drive For Five" ended in the 1984 Stanley Cup Final against the Wayne Gretzky-led Edmonton Oilers. The defeat gave way to hockey's next dynasty and snapped the Islanders' streak of 19 consecutive playoff series wins - still a record in North American professional sports.

6. New York Yankees

Years of dynasty: 1996-2001
Championships won: 4

With their "Core Four" of Derek Jeter, Andy Pettitte, Jorge Posada, and Mariano Rivera, along with legendary skipper Joe Torre, the New York Yankees were a turn-of-the-millennium juggernaut. During their six-season reign, every World Series but one saw them represent the American League. The team's 114 wins during the 1998 regular season still stand as the third-highest total in MLB history.

The Yankees' pitching during that dynasty is another element that perfectly encapsulates the team's dominance. Of the 23 perfect games thrown in MLB history, only two were recorded between 1996 and 2001. They were both thrown by Yankees pitchers: David Wells in 1998 and David Cone in 1999.

5. Edmonton Oilers (1983-90)

Years of dynasty: 1983-90
Championships: 5

Equipped with two of the greatest players ever in Gretzky and Mark Messier, the Oilers dominated the NHL during the '80s. Gretzky was unlike anyone else in hockey history; from 1983-84 to his final season in Edmonton in 1987-88, "The Great One" tallied 314 goals, 646 assists, and won both the Hart Memorial Trophy and Art Ross Trophy four times. Even after the team incredulously dealt Gretzky away in 1988, Messier carried the Oilers back to hockey's peak in 1990, sweeping Gretzky's Los Angeles Kings en route to another Stanley Cup win.

Edmonton hasn't won a Cup since then, but their dynasty hasn't been forgotten. In 2017, the 1984-85 squad was voted by fans as the greatest NHL team ever assembled.

4. Los Angeles Lakers

Years of dynasty: 1979-89
Championships won: 5

Despite the Los Angeles Lakers' roster already featuring an all-time great in Kareem Abdul-Jabbar, it was a rookie in Magic Johnson who got the franchise over the hump in 1979-80 and kick-started one of the greatest eras in NBA history. With Johnson pulling the strings for the up-tempo "Showtime" Lakers, the club won five championships in eight Finals appearances during a 10-year span.

Hall of Famer James Worthy joined the fray in 1982-83, further bolstering an embarrassment of riches at the offensive end. Meanwhile, head coach Pat Riley was the perfect person to manage the team's personnel. With his slicked-back hairstyle and Armani suits, there wasn't another bench boss who could have embodied the Hollywood culture quite like Riley.

3. Boston Celtics

Years of dynasty: 1956-69
Championships won: 11

After drafting Bill Russell second overall in 1956, the Boston Celtics immediately ushered in the most successful period in franchise history. With icons like Bob Cousy, John Havlicek, and Tom Heinsohn, among others, playing under Hall of Fame coach Red Auerbach, Boston made the NBA Finals in 10 consecutive seasons. In fact, after Russell was drafted, the only NBA title Auerbach failed to win was in 1958, when the Celtics lost to the St. Louis Hawks in The Finals.

Even after Auberbach retired in 1966, the Celtics continued to win. That was thanks to Russell stepping in as player-coach for the next three seasons and leading the franchise to another two championships.

2. New England Patriots

Years of dynasty: 2001-2019
Championships won: 6

The duo of Tom Brady and Bill Belichick led the New England Patriots to unprecedented success over nearly two decades. With the legendary quarterback and coach in the fold, the club won six Super Bowl championships - including three of the last six - to tie the Steelers for the NFL's all-time lead. After Brady took over as the starter in 2001, the Pats never posted a losing season and failed to register double-digit wins just once. Now, Belichick will look to extend that run of success with a new QB under center.

With Brady and Belichick, New England was always a virtual lock to claim the AFC East, capturing 17 of the past 19 divisional crowns. While the Pats' 2007 campaign didn't have its perfect ending, the team did go 16-0 to become the only undefeated side in NFL history after the regular season expanded to 16 games.

1. Chicago Bulls (1991-98)

Years of dynasty: 1991-98
Championships won: 6

Nobody had a hold on the NBA throughout the '90s like Michael Jordan and his Chicago Bulls did.

After the Bulls finally beat their hated rivals, the Detroit Pistons, in the 1991 Eastern Conference finals - with a sweep, no less - there was no team left that could stop them. Chicago quickly dispatched the Los Angeles Lakers in that year's Finals and then claimed another five using two separate three-peats.

Jordan's minor-league baseball break from 1993-95 and the front office's hesitance to keep the team together past 1998 were the only things that stopped the Bulls from dominating the entire decade.