War conflicts have always attracted the artists’ attention. In this paper we are going to make a synopsis about a series of Goya’s engravings named Los desastres de la Guerra. After that, we are going to review the work of pioneer photographers during the wars in the twentieth century, paying special attention to the Crimean War and the American Civil War. We will be pointing out the different ways photographers worked by digging into the several determinants that affected them. We will also analyse the different relations among avant-garde, Dadaism and power, besides the role of photographers from World Wars I and II. To finish with, and after making a selection of works in order to show how illustrators represent war conflicts, we are going to commentate on the images of a group of works that exemplify the illustrators’ convictions about the horror of war.