This chapter continues the exploration of the gap between legal theories on the conduct of war and enemy aliens on the one hand and the practice of states at war on the other. It focuses first of all on the Franco-Prussian War of 1870–1871 that anticipated the mobilization of the nation-in-arms and examines, in particular, the expulsion of "Germans" from Paris and Strasbourg in the summer of 1870, the consequences of the expulsion and the lively debate among international lawyers it sparked. The chapter continues with an analysis of the Russo-Ottoman War of 1877–1878, concentrating on the emergence of a humanitarian discourse in order to legitimize intervention. Then it moves east to take into consideration the treatment of enemy aliens and the accompanying discourses on civilization in the Sino-Japanese War (1894–1895) and in the Russo-Japanese War of 1904–1905. This chapter also delves into the novelties that occurred in the field of international law and international relations with the signing of the Geneva Convention, the foundation of the Institute of International Law in Brussels, the two Conferences at The Hague in 1899 and 1907. The final part of the chapter concentrates on the Balkan conflicts of 1912–1913 and the atrocities against civilians.