ABSTRACT
In 1870-1871 Karl Marx and Friedrich Engels had warned the Germans that the annexation of Alsace-Lorraine would lead to a Franco-Russian alliance against Germany. A brief Balkan war at the end of 1885 was the occasion for Engels to voice in stark terms his abhorrence of war at that stage. The belligerents were Bulgaria and Serbia. The right attitude of the proletariat to militarism and war was the main subject of debate at the Second International Socialist Congress, held in Brussels in August 1891. There was agreement that war – any war – would be a disaster and that it was the duty of the working class and all socialists to do everything to prevent a conflict in which the main European powers would be involved. So Engels, while intensely disliking Bismarck and his policy, was adamant about the need to defend Bismarck's main achievement, the unification of Germany.
