Dundalk survived a nervy finish at Casey's Field to hold out for a result which secured their return to European football next season.
First-half goals from David McMillan and Runar Hauge put Stephen O’Donnell’s side in the driving seat but an Ethon Varian header with a minute remaining briefly threatened to spoil the party.
In the end the home side held out for a result which will see them take part in next summer’s Europa Conference League qualifiers.
Having been in Europe for eight seasons in a- row prior to this one, O’Donnell has achieved his objective in his first year in charge at Oriel Park.
While Dundalk can still potentially finish second, this result - coupled with Sligo Rovers’ win over St Patrick’s Athletic at Tthe Showgrounds - means that the Inchicore outfit cannot catch them for third place.
For Bohs, Declan Devine will be pleased with large aspects of his side’s play, having dictated proceedings for the most part but his wait for a first win since succeeding Keith Long will extend into a third game at home to Sligo Rovers on Sunday week.
It was the visitors who started on top with Liam Burt forcing a good save from Nathan Shepperd inside the opening four minutes before Andy Boyle was called upon into a redeeming block to deny Kris Twardek six minutes later after he had coughed up possession all too easily to James McManus, who then set the Canadian winger away.
Burt then headed into the side-netting after a Jordan Flores corner was kept alive by Rory Feely on 13 minutes before Dundalk hit the front against the run of play on 21 minutes.
Bohs had reason to feel aggrieved after Jordan Doherty was penalised for what looked a stumble by Ryan O'Kane but the hosts punished them as McMillan stepped up to curl a superb free kick past 17-year-old debutant goalkeeper Reece Byrne to the top left hand corner.
The Gypsies then went close to a response seven minutes later when Feely’s header from Flores’ corner had to be turned around the post by Shepperd.
Dundalk then doubled their advantage on 39 minutes with a superb goal on the break. It was initiated by Alfie Lewis, who won possession back before finding McMillan. He then released Hauge, who did well to race clear of Max Murphy before slotting under Byrne.
The Norwegian, on loan from Hibernian, went close to his second seven minutes after the break after breaking away on the right but on this occasion his effort was touched over by Byrne.
Shepperd, who picked up Dundalk’s Players’ Player of the Year award before kick-off, then had to be at his best to preserve his side’s 2-0 lead on 59 minutes when he made a super save at close range to deny Ciaran Kelly after Feely had kept alive another Flores corner.
The visitors dominated possession after that but a David McDaid shot that curled just wide on 75 minutes was about as close as they came to pulling a goal back.
Flores also had a free kick touched over by Shepperd with five minutes to go with Feely heading tamely wide from the resulting corner.
They would eventually break the Louth side’s resolve as Varian headed in from Flores’s corner - Bohs’ 11th of the night - with a minute remaining.
Doherty then went close to breaking Dundalk’s hearts when he pulled a shot agonisingly wide but the Lilywhites held out to secure their return to European football next season.
Dundalk: Nathan Shepperd; John Mountney, Lewis Macari, Andy Boyle, Darragh Leahy; Alfie Lewis, Sam Bone; Runar Hauge (Joe Adams 64), Steven Bradley, Ryan O’Kane (Keith Ward 77); David McMillan (John Martin 76).
Bohemians: Reece Byrne; Jordan Doherty, Rory Feely, Ciaran Kelly, Max Murphy (Jamie Mullins 79); James McManus, Jordan Flores; Kris Twardek (Declan McDaid 48), James Clarke, Liam Burt; Ethon Varian.
Referee: Adriano Reale (Kildare).
