Celtic looked dominant as they went in search of a second, but the decisive goal did not come until early in the second half. Teenager Liam Henderson, who replaced Adam Matthews at the interval, converted the ball past Gallagher with conviction to give the Hoops a two-goal lead after 48 minutes.
The third soon followed courtesy of Stefan Johansen, with the Norwegian rifling a low shot into the back of the net after striding into the box and all but sealing the title for Neil Lennon's men.
Celtic soon regained their three-goal cushion in added time through Stokes who added his second, firing the ball past Gallagher into the top corner to make it 4-1.
There was still time for Chris Commons to score a fifth to round off a memorable night for the Hoops, slotting it through the legs of the goalkeeper to complete the scoring and ensure the title would remain at Celtic Park.