The path to the Stanley Cup is going through one of hockey’s signature rivalries this spring, with the Calgary Flames and Edmonton Oilers squaring off in the NHL’s Western Conference semifinals. (The Flames took Game 1 in a wild 9-6 shootout on Wednesday night; Game 2 is Friday night in Calgary.) Not only will the series determine who carries the banner for all of Canada in hopes of ending its painful 29-year Cup drought,⁷ but it represents a fierce clash between provincial neighbors with almost as much history, and hostility, on the ice as off.

So with the help of our Elo ratings, let’s take a tour through the history of the rivalry, tracing the rise and fall — and rise again — of Western Canada’s most bitter foes.

Though the two franchises started out at the same time, they took very different paths to what would eventually become an iconic rivalry. The Oilers first played in 1972 as a charter member of the upstart World Hockey Association and were known at the time as the Alberta Oilers, under an early plan (which never materialized) to split home games between Edmonton and Calgary.⁸ Rooting itself explicitly in Edmonton — and changing to a more familiar name — starting in 1973, the team still found little success in the WHA … until it bought the rights to a skinny 17-year-old prospect named Wayne Gretzky. With Gretzky leading the way as a rookie in 1978-79, Edmonton nearly won the WHA’s last Avco Cup title, and his Oilers were absorbed into the NHL when the leagues merged in 1979.

Meanwhile, the Flames were born in 1972 as well, beginning their NHL life in the unconventional hockey market of Atlanta. Though largely forgotten now, the Atlanta Flames had some pretty good seasons in the mid-to-late 1970s — and in a certain sense, they can be seen as an early audition for the NHL’s later, more successful forays into the American South. But when financial losses mounted for Flames ownership in 1980, the team was sold to Canadian investors and moved northwest. Thus it came to be that the NHL had two Alberta-based franchises, destined to battle across the deep cultural divide that has always separated Edmontonians from Calgarians.

The conflict was fierce from the start, with one of the most penalty-filled games in the history of the rivalry taking place in just the second Edmonton-Calgary game ever. The teams avoided playoff confrontation early in their time as neighbors — until 1983 and 1984, that is, as the Oilers eliminated the Flames en route to the Stanley Cup final both years. (Game 7 of the 1984 division finals was a particularly wild affair, with Calgary taking a 4-3 lead midway through before Edmonton scored four unanswered goals to advance — a stepping stone on the path to the Oilers’ first Cup.) While the two teams had been on the same level in Elo at the beginning of the 1980s, the emergence of Gretzky and Edmonton’s high-scoring offense gave the Oilers a dynasty — and a clear edge in the Battle of Alberta by the middle of the decade.

But things got more competitive as the Flames began building a strong talent base of their own. Calgary improved from minus-3 in goal differential in 1984 to plus-61 in 1985 on the strength of the NHL’s second-best offense, trailing only Edmonton. And when the two teams matched up again in the playoffs in 1986, Oilers defenseman Steve Smith scored an infamous own-goal in Game 7 — accidentally banking the puck off netminder Grant Fuhr’s skate on a pass from behind the net — providing Calgary the margin to finally beat their rivals in the division finals. (The Flames would go on to lose to Montreal in an all-Canadian Cup final.)

That was a rare miscue for Edmonton: It marked the only time from 1984 through 1988 that the Oilers didn’t win the Cup. As much as Calgary improved over the course of the ’80s, Edmonton usually was a step ahead; even when the Flames finished a franchise-best No. 2 in Elo in 1987-88, the Oilers were No. 1. But Gretzky’s shocking departure for Los Angeles in August 1988 changed the rivalry — and the Flames seized on the opportunity to surpass their rivals, closing out the decade with the franchise’s first (and, for now, only) Stanley Cup triumph.

Somewhat surprisingly, the Oilers bounced back from their post-Gretzky downturn to begin the 1990s, capitalizing on their former captain’s own first-round win (with the L.A. Kings) over Calgary to then sweep Los Angeles in the following round and ultimately win yet another Cup. For those counting, that meant either Edmonton or Calgary had won four consecutive championships and six of the previous seven. The Battle of Alberta was effectively the battle to control the entire NHL.

But little did the teams know that would be the last Cup for either franchise in three decades and counting. As the economics of the NHL shifted during the 1990s to favor higher-payroll teams — and, relatedly, the American dollar — the Flames and Oilers fell behind. From 1992-93 through 2002-03, the teams combined to win only two playoff series: Edmonton’s pair of improbable seven-game victories over No. 2 seeds in 1997 (the Dallas Stars) and 1998 (the Colorado Avalanche). But while Oilers goalie Curtis “Cujo” Joseph was brilliant in both upsets, the decade as a whole was a time of decline and mediocrity in Alberta.

That trend carried over into the 2000s at first, reaching its nadir when neither team made the playoffs at all in 2001-02 — the first time that was true in the rivalry’s history. But each franchise was due for a moment of excitement, however brief.

The Flames had their turn first, improving by nearly 20 points in the standings under former (and, incidentally, current) coach Darryl Sutter in 2003-04. Hall of Fame winger Jarome Iginla finally had the goaltending help — in the form of Miikka Kiprusoff — to power a deep postseason run, and Calgary even held a 3-2 lead over the Tampa Bay Lightning in the Cup final before losing a double-OT heartbreaker at home in Game 6 and another tight contest in Game 7.

After a lockout torpedoed the entire 2004-05 season — and radically changed the economics of the league yet again — Edmonton went on a run of its own behind the standout play of defenseman Chris Pronger and journeyman goalie Dwayne Roloson (a former Flame!). Falling behind three-games-to-one against the Carolina Hurricanes in the 2006 Stanley Cup final, the Oilers rallied to force a Game 7, though they lost on the road to match their rivals’ fate from two years earlier.

The Battle of Alberta had seen both of its competitors come close to winning championships in the mid-2000s. But instead of serving as the prelude to another era of 1980s-style dominance, those Cup final runs were mostly a mirage. Edmonton would miss each of the next 10 postseasons, and Calgary failed to muster another series win for nearly as long.

Which brings us to the current era of the rivalry. The Flames have been one of the most inconsistent teams in the league since the mid-2010s, bouncing between decent seasons and bad ones across multiple coaches and an influx of younger talent such as Johnny Gaudreau, Matthew Tkachuk and Elias Lindholm. The Oilers spent most of the 2010s squandering draft picks, making horrible transactions or generally wasting their chances to build around the once-in-a-generation talent of Connor McDavid.

And yet, both franchises have been on the rise recently. Calgary was one of the NHL’s best teams throughout the 2021-22 regular season, with a deep roster, plenty of star power and a rock-solid goalie in Jacob Markstrom. Edmonton received its typical 1-2 superstar punch from McDavid and Leon Draisaitl, but the Oilers also finished the regular season as the best stretch-run team in the league according to Elo. Along those lines, both clubs were among the top three in goal differential over the second half of the schedule. These teams were in good form for their first playoff meeting since 1991, despite both requiring seven games to dispatch lower-seeded opponents in Round 1, and that showed with 15 total goals in Game 1.

After Calgary’s win, our model gives the Flames a 69 percent chance of winning the series and moving on to the Western Conference final. But if the history between these teams is any indication, anything can happen from here on out. In many ways, this series has been decades in the making — and not just because of the cartoonish, 1980s-style scoreline of the opener. While Alberta is no longer the center of the hockey universe it once was, the path to the Stanley Cup will still run through the province. And that means this rivalry is officially back as one of hockey’s best.

Check out our latest NHL predictions.