Why? Because he completely destroyed the old political division of Western and Central Europe, proving, oddly enough for a military dictator, that the power of repressive or oppressive states can be brought to nothing. In the process he also re-organized borders around, in part along ethnic lines. By doing so, he acknowledged the rights of people to, if not rule themselves, be considered a Nation as such.
Despite being ultimately defeated, his actions in Europe ultimately (among other things of course) led to the contemporary Europe we know today.
Despite being ultimately defeated, his actions in Europe ultimately (among other things of course) led to the contemporary Europe we know today.