Why did many european nations quickly join world war i following the assassination of archduke ferdinand in 1914?

They had pledged to fight with other countries.

Explanation:

After the death of archduke Ferdinand in 1914 bunches of nations immediately joined World War I since they had officially swore to battle with nations according to their own allegiances. The territory for war was basically set, and unions were at that point made, the interests were known and on the table for couple of years before that, so the death of archduke Ferdinand was only the point that denoted the beginning stage of the practically unavoidable war.

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`stare decisis is a legal doctrine that obligates courts to follow historical cases when making a ruling on a similar current or future case. stare decisis ensures that cases with identical facts be approached in the same way, unless overruled by the same court or a higher court such as the us supreme court. simply put, it binds courts to follow legal precedents set by previous decisions.

stare decisis is a latin term meaning "to stand by that which is decided".