In the 19 th century Irish historical novel,writers used picturesque landscape based on the spatial fabric of historical scenes and developed a changing style that was dominated by Neoclassicism as its primary influence.The evolution of such a style not only endowed the Picturesque with Irishness,but also opened the way to assessing historical space selfreflexively.Irish Picturesque adopted some patterns of topographical discourse for the representation of landscape.This made core issues of land cultivation,production relation,and institutional evolution,thus effectively revealing the root cause for the turbulent Irish history.Also,under the sweeping influence of the capitalist system,grotesque urban landscape started to appear in the Irish historical novel.By adopting the aesthetic principle of "concordia discors" creatively,writers managed to facilitate a reciprocal assimilation between Picturesque and Grotesque in order to cultivate the unified historical space for the country and city as well in Irish historical novel.