In 1953, a Baltimore based group led by Carroll Rosenbloom won the rights to a new Baltimore National Football League franchise. Rosenbloom was awarded the remains of the Dallas Texans. The Colts were the first NFL team to have cheerleaders and a marching band. The Colts were named after Baltimore’s annual Preakness Stakes which is why many fans are bitter that Indianapolis retained the Colt team name.

The 1958 National Football League Championship Game was the 26th NFL championship game, played on December 28 at Yankee Stadium in New York City. It was the first NFL playoff game to go into sudden death overtime. The final score was Baltimore Colts 23, New York Giants 17, and the game has since become widely known as “The Greatest Game Ever Played.”

It marked the beginning of the NFL’s popularity surge, and eventual rise to the top of the United States sports market. A major reason was that the game was televised across the nation by NBC. Baltimore receiver Raymond Berry recorded 12 receptions for 178 yards and a touchdown. His 12 receptions set a championship record that stood for 55 years.

The 1959 National Football League Championship Game was the 27th NFL championship game, played on December 27 at Memorial Stadium in Baltimore, Maryland.

It was a rematch of the 1958 championship game that went into overtime. The defending champion Baltimore Colts (9–3) again won the Western Conference, while the New York Giants (10–2) repeated as Eastern Conference champions. The Colts were favored to repeat as champions by 3½ points.

This game also went down to the last quarter, but the Colts did not need any heroics in overtime. Trailing 9-7 at the start of the fourth quarter, Baltimore scored 24 straight points and won, 31–16.

This was the only NFL championship game played in Baltimore.

Super Bowl V, the fifth edition of the Super Bowl and first modern-era National Football League (NFL) championship game, was an American football game between the American Football Conference (AFC) champion Baltimore Colts and the National Football Conference (NFC) champion Dallas Cowboys to decide the NFL champion for the 1970 season. The Colts defeated the Cowboys by the score of 16–13. The game was played on January 17, 1971, at the Orange Bowl in Miami, Florida, the first Super Bowl game played on artificial turf, on first-generation Poly-Turf.

The 1968 National Football League championship game was the 36th annual championship game. The winner of the game represented the NFL in the third AFL-NFL World Championship Game also called the Super Bowl. The NFL title game was held December 29 at Cleveland Municipal Stadium in Cleveland, Ohio.

Rosenbloom traded the Colts franchise to Robert Irsay on July 13, 1972 and received the Los Angeles Rams in return. Under the new ownership, the Colts did not reach the postseason for three consecutive seasons after 1971, and after the 1972 season, starting quarterback and legend Johnny Unitas was traded to the San Diego Chargers.

Irsay assumed ownership of the Baltimore Colts on July 13, 1972 after acquiring the Los Angeles Rams from the estate of Dan Reeves and swapping franchises with Carroll Rosenbloom, all made official on the same day. His last-minute US $19 million bid for the Rams was $2 million more than that of Hugh Culverhouse. Irsay’s majority share in the Colts was initially 51%, with Willard Keland of Racine, Wisconsin owning the rest. He additionally announced the appointment of Joe Thomas as Baltimore’s new general manager, succeeding Don Klosterman who accompanied Rosenbloom to Los Angeles.

The Colts finished 0–8–1 in the strike-shortened 1982 season, thereby earning the right to select Stanford quarterback John Elway with the first overall pick. Elway, however, refused to play for Baltimore, and using leverage as a draftee of the New York Yankees baseball club, forced a trade to Denver. Behind an improved defense the team finished 7–9 in 1983, but that would be their last season in Baltimore.

The city of Indianapolis, Indiana, made an offer for the Colts franchise to move there. Baltimore was unsuccessful at persuading them to stay, so the city government attempted to get the state legislature to condemn the Colts franchise and give ownership to another group that would promise to keep the Colts in Baltimore. Oakland, California had just had some success in court trying the same tactic with the Oakland Raiders. Under the threat of eminent domain from the city of Baltimore, the franchise relocated to Indianapolis in the middle of the night on March 29, 1984. The city of Baltimore did not give up and sued to condemn the franchise anyway and seize ownership. Baltimore did not prevail in court, but eventually acquired a new NFL team in 1996 with the establishment of the Baltimore Ravens following the Cleveland Browns relocation controversy.