It has exercised a very appreciable influence upon foreign painting.  Among the principal painters attracted by its ideas and research, we must mention, in Germany, Max Liebermann and Kuehl; in Norway, Thaulow; in Denmark, Kroyer; in Belgium, Theo Van Rysselberghe, Emile Claus, Verheyden, Heymans, Verstraete, and Baertson; in Italy, Boldini, Segantini, and Michetti; in Spain, Zuloaga, Sorolla y Bastida, Dario de Regoyos and Rusinol; in America, Alexander, Harrison, Sargent; and in England, the painters of the Glasgow School, Lavery, Guthrie and the late John Lewis Brown.  All these men come within the active extension of the French movement, and one may say that the honour of having first recognised the truly national movement of this art must be given to those foreign countries which have enriched their collections and museums with works that were despised in the land which had witnessed their birth.  At the present moment the effects of this new vision are felt all over the world, down to the very bosom of the academies; and at the Salons, from which the Impressionists are still excluded, can be witnessed an invasion of pictures inspired by them, which the most retrograde juries dare not reject.  In whatever measure the recent painters accept Impressionism, they remain preoccupied with it, and even those who love it not are forced to take it into account.

The Impressionist movement can therefore now be considered, apart from all controversies, without vain attacks or exaggerated praise, as an artistic manifestation which has entered the domain of history, and it can be studied with the impartial application of the methods of critical analysis which is usually employed in the study of the former art movements.  We shall not pretend to have given in these pages a complete and faultless history; but we shall consider ourselves well rewarded for this work, which is intended to reach the great public, if we have roused their curiosity and sympathy with a group of artists whom we consider admirable; and if we have rectified, in the eyes of the readers of a foreign nation, the errors, the slanders, the undeserved reproaches, with which Frenchmen have been pleased to overwhelm sincere creators who thought with faith and love of the pure tradition of the national genius, and who have for that reason been vilified as much as if they had in an access of anarchical folly risen against the very common sense, taste, reason and clearness, which will remain the eternal merits of their soil.  This small, imperfect volume will perhaps find its best excuse in its intention of repairing an old injustice and of affirming a useful and permanent truth:  that of the authenticity of the classicism of Impressionism, in the face of the false classicism of the academic world which official honours have made the guardian of a French heritage, whose soul it denied and whose spirit it deceived with its narrow and cold formulas.