How were the sebians involved n the start of world war 1?

The Serbians played a crucial role in the onset of World War I when a Bosnian Serb nationalist, Gavrilo Princip, assassinated Archduke Franz Ferdinand of Austria-Hungary on June 28, 1914. This event escalated tensions between Austria-Hungary and Serbia, leading Austria-Hungary to issue an ultimatum to Serbia. When Serbia's response failed to satisfy Austria-Hungary's demands, it declared war on Serbia on July 28, 1914, triggering the wider conflict that engulfed Europe. This chain of events ultimately set off alliances and mobilizations that led to the full-scale war.