Acadian was a make of automobile produced by General Motors of Canada from 1962 to 1971. The Acadian was introduced so that Canadian Pontiac-Buick dealers would have a compact model to sell, since the Pontiac Tempest was unavailable in Canada.
Basically it was a mix of Chevrolet and Pontiac bits and pieces. In this case a first generation Chevy II with Pontiac grille and trim.