For the sixth consecutive season, the Cowboys had a first-place finish. The Cowboys won their second-consecutive NFC championship, then defeated the Miami Dolphins in Super Bowl VI to capture their first Super Bowl championship. It was the team's first championship of any kind. They were the first team from the NFC to win a Super Bowl since the 1970 merger of the National Football League and the American Football League, and subsequently, also the first team from the NFC East division to win the title.
The team entered the season still having the reputation of "not being able to win the big games" and "next year's champion". The Super Bowl V loss added more fuel to that widely held view. As in the previous season, Dallas had a quarterback controversy as Staubach and Craig Morton alternated as starting quarterback (in a loss to the Bears in game 7, Morton and Staubach alternated plays). The Cowboys were 4–3 at the season midpoint. But after head coach Tom Landry settled on Staubach, the Cowboys won their last seven regular season games to finish with an 11–3 record.
Staubach finished the regular season as the NFL's top rated passer (101.8) by throwing for 1,882 yards, 15 touchdowns, and only 4 interceptions. He was also a terrific rusher, gaining 343 yards and 2 touchdowns on 41 carries. Said Cold Hard Football Facts of Staubach's 1971 season, "Staubach finally out-jockeyed Craig Morton for the starting gig with the Cowboys in 1971 and instantly produced one of the greatest passing seasons in history. The numbers are not big and gaudy, but they were ruthlessly efficient –- the 104.8 passer rating truly amazing in a season in which the average rating was 62.2. His 8.9 [yards-per-attempt] in the regular season is phenomenal in any era of the NFL, as was his 18 [touchdowns] against a meager 4 [interceptions] (including postseason). The Cowboys did not lose a single one of Staubach's 13 starts in 1971 and –- most impressively –- he lifted the proverbial "team that couldn't win the big game" to its long-awaited first NFL championship.[...]"
Dallas also had an outstanding trio of running backs, Walt Garrison, Duane Thomas, and Calvin Hill, who rushed for a combined total of 1,690 yards and 14 touchdowns during the season. Garrison led the team in receptions during the season. (Thomas, upset that the Cowboys would not renegotiate his contract after his excellent rookie year, had stopped talking to the press and to almost everyone on the team). Wide Receivers Bob Hayes and Lance Alworth also provided a deep threat, catching a combined total of 69 passes for 1,327 yards and 10 touchdowns. The offensive line, anchored by all-pro tackle Rayfield Wright, Pro BowlersJohn Niland and Ralph Neely, and #64 Tony Liscio who was coaxed out of retirement by Tom Landry after Ralph Neely got injured off the field, was also a primary reason for their success on offense. (Neely had broken his leg in November in a dirt-bike accident, and was replaced first by Gregg and then by Tony Liscio, who came out of retirement.)
The Dallas defense (nicknamed the "Doomsday Defense") had given up only one touchdown in the last 25 quarters prior to the Super Bowl. Their defensive line was anchored by Pro Bowl defensive tackle Bob Lilly, who excelled at pressuring quarterbacks and breaking up running plays. Dallas also had an outstanding trio of linebackers: Pro Bowler Chuck Howley, who recorded 5 interceptions and returned them for 122 yards; Dave Edwards 2 interceptions; and Lee Roy Jordan, who recorded 2 interceptions. The Cowboys secondary was led by 2 future hall of fame cornerbacks Herb Adderley (6 interceptions for 182 return yards) and Mel Renfro (4 interceptions for 11 yards). Safeties Cliff Harris and Pro Bowler Cornell Green also combined for 4 interceptions.After the 1971 Bob Lilly would play in the last of his last pro bowl despite being selected after the 1972 and 1973 seasons.Lilly would also score his final career touchdown in a 42–7 smashing of The Philadelphia Eagles.Lilly would retire with the NFL record of scoring the most tds by a defensive lineman with 4.
September 26, 1971 – Herb Adderley became the first Cowboy to have three interceptions in one game.
The Cowboys earned their first win on Monday Night Football by defeating the New York Giants 20–13 which also the last game The Cowboys played in The Cotton Bowl.