North American expansion team reaching Championship final in inaugural year

Baltimore Stallions:

In 1994 the Baltimore Stallions made it to the Grey Cup finals, in their inaugural year, making them the most successful American team in CFL history. Despite not winning the 1994 Grey cup, they lost by 3 points to the BC Lions, they went on to win the Grey cup in 1995 against Calgary Stampeders

Chicago Fire Soccer Club:

In 1998 the Chicago Fire Soccer Club began as one of the Major League Soccer's (MLS) first expansion teams. That year, they won both the MLS Cup as well as the U.S Open cup, achieving a double, where a soccer team has won a country's top tier division and its primary cup competition in the same season.

Minneapolis Lakers:

The 1947-48 season was Minneapolis Lakers inaugural season in the NBA and they won the National Basketball League championship in a 3-1 series final against the Rochester Royals. The Lakers went on to win their division and championship the following 1948-49 season as well.

For the 1967-68 season, the NHL expanded from 6 to 12 teams. All the new teams were grouped in the West Division. The division champions were the Montreal Canadiens (original 6) and the St. Louis Blues (expansion team). The Canadiens won the Stanley Cup Finals 4-0.

The 1973-4 Flyers were the first of the expansion teams to win the Cup.

In 1949 The AAFC(All-American Football Conference) closed it's doors or went bankrupt and the NFL invited the Browns, and 2 others, into their league in 1950. In the Browns first Season they went 10-2 and beat the LA Rams(on a last minute field goal) 30-28 to win their first of four National Football League championships. While not truly an "expansion" team it was their first year in the NFL.

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