28 июня 1914 года сербский гимазист Гаврило Принцип убил эрцгерцога Франца Фердинанда и его супругу, что послужило поводом к I Мировой войне

At that day, Serbians and Bosnians remembered the warriors of Prince Lazar of Serbia killed in the battle of Kosovo 525 years ago. After that, Serbia (and later, Bosnia and Herzegovina) became vassals of the Ottoman Empire. At the end of the 19th century, the countries gained freedom and became kingdoms. For Bosnia and Herzegovina, the freedom did not last long: the country was annexed by the Austro-Hungarian Empire. The arrival of Archduke Franz Ferdinand, the heir to the throne and a direct culprit of the annexation, was an insult to the Bosnians. The revolutionary organization Young Bosnia issued him a death sentence. The gun was given to the 18-year-old Gavrilo Princip. The assassin was arrested but not killed: only people over 20 could be sentenced to death. Four years later, Yugoslavia’s national hero died in prison. By that time, 10 million people were killed in the battles of World Wat I, and other 20 million were wounded or shell-shocked.