Vienna University was founded in 1365 by the Habsburg Rudolf IV as a rival to the university at Prague, which had been established by his father-in-l-aw, Emperor Charles IV. Today it is the oldest university in the German-speaking countries. During the Middle Ages the emphasis was on teaching rather than research. In 2008 more than 70,000 students were registered at the University of Vienna. The university library today holds more than six million titles.