Vagabonds lifted the final piece of domestic silverware with a 31-8 win over Southern Nomads at a sunny Glencrutchery Road.
Nomads needed to win by 14 points or more to take the title and they were soon under the cosh when Steve Gawne put Vagas 5-0 up in just the fourth minute.
Danny Williams pulled a penalty back for Nomads to make it 5-3 but, on the stroke of half-time, Ross Pullman added a second try for Vagas which Kieran Lever converted from the touchline.
Jason Bowden and Bryan Kennaugh both added tries for Vagas in the second half, with Lever converting both to rack up a 26-3 lead.
Nomads grabbed a late consolation try through Andy Joughin but Vagas put the result with a late try from Peter Bates.
In the Shimmin Wilson Manx Bowl, Ramsey B grabbed the runners-up spot with an entertaining 50-34 win over Emerging Nomads.
Mikey Craine was the star for Ramsey, bagging two tries and five conversions for a personal 20 point haul.
Nomads were right in the game and their man of the moment was full back Dave Edge who weighed in with two tries and two conversions.
There were also tries from Kenny Tasia, Dave Prince, Kieran Stephens and Wig Bregazzi.