The Beaumont car grew out of the 1964-65 Acadian Beaumont model, which was based on the contemporary Chevrolet Chevy II (Nova), then Chevelle. These Beaumonts featured the Chevrolet Chevelle body with minor styling revisions, including different taillights and a Pontiac-style split grille. The interior used the dash panel from the (U.S.) Pontiac Tempest/LeMans/GTO series.
From 1966, the Acadian name was dropped and Beaumont became a standalone marque, still sold by Pontiac-Buick dealers. The cars sported a new emblem, based on Pontiac's arrowhead motif with two red maple leaves added. They featured the same powerplants as the Chevelle, including the OHV inline six-cylinder engine, and a variety of small- and big-block V8s. The V8 engine choices included small-block 283, 327, and later 350 cubic-inch versions, while the Mark IV big-block could be ordered in its 396 cubic inch displacement. 3- and 4-speed manual transmissions were available, as were the 2-speed Powerglide and 3-speed Turbo-Hydramatic automatics.
The SD (Sport Deluxe) models were equivalent to the Chevelle Super Sport trim level, and featured bucket seats and center console, as well as SD body striping and trim. The SD396 models are the most desirable Beaumonts today. Few were built, however, and most succumbed to the harsh Canadian winter climate, which makes them significantly more rare than equivalent Chevelles and desirable to some collectors. The SD series was available in both 2-door hardtop and convertible body styles. In addition to the SD series, the Beaumont line included Custom and Deluxe lines.
The Beaumont continued through the 1969 model year, after which it was replaced in the Canadian market by the Pontiac LeMans.