The 1966 Dallas Cowboys season was the seventh for the franchise in the National Football League. It involved the 10–3–1 Cowboys qualifying for the NFL post-season for the second time in franchise history, by winning the NFL Eastern Conference title, before losing the NFL Championship Game to the eventual Super Bowl champion Green Bay Packers.
With the growth in popularity of televised NFL games, the league began looking for a second team in addition to the Detroit Lions, to host an annual Thanksgiving Day game. Every team turned down the offer, except for the Dallas Cowboys. General Manager Tex Schramm recognized this as an opportunity for the franchise to increase its popularity and establish its own Thanksgiving Day game tradition.
In 1966, the Cowboys who had been founded six years earlier, adopted the practice of hosting Thanksgiving games. It is widely rumored that the Cowboys sought a guarantee that they would regularly host Thanksgiving games as a condition of their very first one (since games on days other than Sunday were uncommon at the time and thus high attendance was not a certainty). Since then, the two "traditional" Thanksgiving Day pro football games have been in Detroit and Dallas.