(A) Nationalist movements in the Balkans
(B) ** The assassination of Archduke Franz Ferdinand
(C) The sinking of Lusitania
(D) The rise of Vladimir Lenin in Russia
EXPLANATIONS BELOW
Concept note-1: -When it was learned that the heir-apparent to the Austrian throne, Franz Ferdinand, was scheduled to visit Sarajevo in June of 1914, the Black Hand decided to assassinate him because of his perceived threat to Serbian independence.
Concept note-2: -Just hours after narrowly escaping an assassin’s bomb, Archduke Franz Ferdinand, the heir to Austro-Hungarian throne and his wife, the Duchess of Hohenberg, are killed by Gavrilo Princip. A month later, Austria-Hungary declares war on Serbia and Europe rapidly descends into chaos. Read more about it!
Concept note-3: -Although the assassination of Archduke Ferdinand was the spark that caused Austria-Hungary to strike the first blow, all the European powers quickly fell in line to defend their alliances, preserve or expand their empires and display their military might and patriotism.