The Balkan crisis of 1914 led to the ww1. how? the immediate cause of ww1 was the assassination of archduke Ferdinand and his wife in Serbia, a Balkan state that had become autonomous after the firsts Balkan wars a decade earlier. The Balkan wars had resulted to loss of Ottoman powers as well as those of Austria Hungary, in addition to fueling a number of rivalries and tensions. The reason for assassination of the Austrian heir was the Balkan war and nationalistic tensions by Balkans.