Question

Who declared the 4th Great Ninja War and Why?​

Answer 1

Tobi declares the Fourth Shinobi World War against the Five Great Shinobi Countries. Its beginning was declared by Tobi when the five Kage and the leader of the Land of Iron unanimously refused to surrender the Eight and Nine-Tails for his Eye of the Moon Plan.

Answer 2

Tobi declared the 4th Great Ninja War.

It declared when the five Kage and the leader of the Land of Iron unanimously refused to surrender the Eight and Nine-Tails for his Eye of the Moon Plan.

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