The correct answer is Austria-Hungary
The borders of Austria and most European countries have been formed over hundreds of years. Whenever they could, rulers and dynasties sought to expand their domains. The Habsburg family, one of the most powerful in Europe, governed a large area that was named Austria. Over time, the region of Hungary, which was in the territory of the Habsburgs, began to demand more autonomy. In 1867, the Habsburgs were forced to divide their empire into two parts. Thus a new empire emerged, the Austro-Hungarian. The two nations formed a dual monarchy (one king for two countries), which remained until 1918.
I'd say pollution or disease.
