Edgeworth is regarded as a pioneer in the development of the regional novel and the use of vernacular language. This study investigates her attitudes towards language and regionalism. It shows, by a detailed discussion of her major Irish texts - Castle Rackrent , Essay on Irish Bulls , Ennui , The Absentee and Ormond - how her intellectual 'Lunar' background, and her life in Ireland during the momentous years of the Union is reflected in the form and language of her writing.