One of Europe's major powers at the time, Austria-Hungary was geographically the second-largest country in Europe and the third-most populous (after Russia and the German Empire). The Empire built up the fourth-largest machine-building industry in the world. With the exception of the territory of the Bosnian Condominium, the Empire of Austria and the Kingdom of Hungary were separate sovereign countries in international law. At its core was the dual monarchy, which was a real union between Cisleithania, the northern and western parts of the former Austrian Empire, and Transleithania (Kingdom of Hungary). Following the 1867 reforms, the Austrian and Hungarian states were co-equal in power. The two countries conducted unified diplomatic and defence policies. For these purposes, "common" ministries of foreign affairs and defence were maintained under the monarch's direct authority, as was a third finance ministry responsible only for financing the two "common" portfolios. A third component of the union was the Kingdom of Croatia-Slavonia, an autonomous region under the Hungarian crown, which negotiated the Croatian–Hungarian Settlement in 1868. After 1878, Bosnia and Herzegovina came under Austro-Hungarian joint military and civilian rule. Anxious about Balkan instability and Russian aggression,