Why was archduke franz ferdinand of austria-hungary a key player in world war 1

Archduke Franz Ferdinand of Austria-Hungary was a key player in World War I because it started as a result of his assassination.

Explanation:

Franz Ferdinand was archduke of Austria, imperial prince of Austria, royal prince of Hungary and Bohemia and, from 1896 until his death, the heir to the Austro-Hungarian throne. His murder in Sarajevo on June 28, 1914, precipitated the declaration of war of Austria against Serbia that unleashed the First World War.

they have different colored collars

might be agreeing to participate ethically with other european nations in the slave trade

or notifying other european nations when taking possession   of african territories