The Toronto Raptors beat the Milwaukee Bucks 100-94 to seal a 4-2 series win and reach the first NBA Finals in their 24-year history.
They will now face defending champions the Golden State Warriors in a series which starts in Toronto on Thursday.
The Raptors are coached by Nick Nurse, who has extensive experience in the British Basketball League.
Star man Kawhi Leonard scored 27 points and a career-best 17 rebounds to help the Canadian team make history.
His side had lost the first two games of the best-of-seven series before recording four wins in a row.
The Bucks started Saturday's game at Toronto's Scotiabank Arena strongly and led by 15 points at one stage in the third quarter before being pegged back.
"It's still surreal to me right now but this is what we've been striving for all season. It's not over yet," Leonard said.
"He inspired us tonight with monster rebounds," Raptors coach Nurse added.
From Derby, Birmingham & Brighton to the NBA Finals
For Nurse, reaching the finals marks the latest chapter in a remarkable rise. The 51-year-old American only realised his dream of leading an NBA team last summer when he took charge of the Raptors.
That came after a journeyman career which has included stints in the BBL at Derby Storm, Birmingham Bullets, Manchester Giants, London Towers and Brighton Bears.
He led the Bullets and Giants to the league title and twice won the BBL coach of the year award, working on a £100,000 budget - in contrast to the $150m (£120m) budget he enjoys at the Raptors.
Disappointed Bucks 'just getting started'
The Bucks had the NBA's best record (60-22) during the regular season and had been favourites to win the Eastern Conference finals against a franchise only formed in 1995.
"This hurts," Bucks coach Mike Budenholzer said. "But what they did in the play-offs tonight against a really good Toronto Raptors team, and to get to the Eastern Conference finals, the regular season, [it's] a special season for us.
"We feel like we're just getting started."