The Cowboys joined the National Football League in 1960. The Cowboys are one of the most successful team in the NFL and in American sports overall. The Cowboys had the longest streak of consecutive winning seasons with 20.The Cowboys were the NFL’s first modern-era expension team. In 1967, the Cowboys finished with a 9-5 record in their first playoff victory, facing the Cleveland Brown. They went on to face the Packers in 1967 NFL Championship game and they won the Super Bowl ll. The game was on December 31, 1967 at Lambeau Field in Green Bay, it turned out to be the coldest NFL game in history (about -13 F with a wind chill). Cowboys remained one of the NFL’s top teams in 1960’s. In 1969, ground was broken on a new stadium for the Cowboys to replace Cotton Bowl.