Tries from Tiernan O'Halloran, Niyi Adeolokun and Matt Healy helped Connacht seal their first ever Pro12 title with a 20-10 victory over Irish rivals Leinster at Murrayfield.
Pat Lam's men were making their maiden final appearance, but showed few nerves as they produced some stunning running rugby to deservedly down the four-time champions.
Leo Cullen's side, meanwhile, missed 18 tackles during a forgettable first-half performance and although they improved marginally after the break, they looked a shadow of the team that thumped Ulster in the semi-finals.
Their solitary try was scored by Sean Cronin and came too late to haul them back into the contest.
Having survived an early onslaught from Leinster, Connacht gradually eased their way into the contest and drew first blood on 13 minutes.
Healy made the initial inroads with a powerful burst and the ball eventually made its way to O'Halloran who shrugged off the attentions of opposite number Rob Kearney en route to the line.
That try seemed to unsettle Leinster who began to look a little disjointed and soon found themselves further behind.
After his colleagues had shown great invention to keep the ball alive in midfield, Adeolokun chipped ahead and then re-gathered to claim his sixth Pro 12 try of the season.
An Alan MacGinty penalty then took Connacht out to a 15-0 lead that they managed to retain until the break.
The scrum was one area where Leinster were in the ascendancy and it was from a scrum penalty that Johnny Sexton finally got them on the board three minutes into the second half.
But Connacht continued to look the more likely and moments after hooker Tom McCartney had been held up inches short of the line by Sexton, MacGinty's grubber sat up perfectly for Healy to gather and touch down.
Replacement Cronin did rumble over for Leinster 12 minutes from time, with Sexton's conversion giving his side a glimmer of hope.
But with skipper John Muldoon very much to the fore, Connacht calmly saw out the final moments to clinch a memorable win.