The Oilers joined the NHL as one of the teams making the switch from the World Hockey Association in 1979, and they were soon followed by the Atlanta Flames moving to Calgary in 1980, making the question of who would reign as the top team in Alberta a hot topic. The Flames were the dominant squad during their inaugural season, making it to the conference finals, while the Oilers were making headlines with their young Wayne Gretzky. The Oilers' Stanley Cup Championship in 1984 set the building blocks for one of the last great dynasties of the NHL. They also won in 1985, 1987, 1988, and 1990, with line-ups that featured legends such as Grant Fuhr, Paul Coffey, and Mark Messier. The Flames did not win their first Cup until 1989, with superstars Lanny McDonald, Doug Gilmour and Mike Vernon leading them.

The Oilers defeated the Flames in the playoffs in 1983, 1984, 1988, and 1991, on their way to two of their five Stanley Cups. However, the Flames did get a measure of revenge; the infamous 1986 Battle of Alberta was decided by Steve Smith's own goal (credited to Perry Berezan). The Flames were favoured in the 1988 playoffs, but the Oilers swept them in 4 games and eventually went on to win the cup. 1991 was last year the teams met in the playoffs, and it came down to the final game to decide the victor. Esa Tikkanen led the underdog Oilers to victory in overtime with his third goal of the game. It is often cited as one of the most exciting playoff series of all time.

Due to the sheer talent and skill exhibited by both teams in the mid to late-1980s, Alberta was considered somewhat of a "Death Valley" for teams coming to play on a road trip, especially those of the other conference. Over the 12 years between the Oilers entrance into the league and their most recent cup in 1990, Alberta teams won 6 championships.