Amegakure bordered the Land of Fire, the Land of Wind, and the Land of Earth.
They could have simply sent Ninja from Kirigakure and Kumogakure to reinforce the Ninja from Konoha and Iwagakure. It would save time and effort, with each group responsible for a few positions and no one getting in anyone else's way.
But this was war! If every member of the Akatsuki attacked the Land of Wind while it had no support, the country might be destroyed before the war was over.
So they had to gather every Ninja and assign them to units based on their Ninjutsu and abilities, ensuring the forces attacking Amegakure from three directions were evenly matched.
It was a massive undertaking. If the strategists from the Five Great Shinobi Villages had not worked day and night to match everyone up, the war might have been delayed for many more days.
In the Land of Fire, the leaders of the Ninja villages watched the Allied Shinobi Forces mass before them.
"Quiet!" Raikage A shouted.
"Let the commander of the Allied Shinobi Forces, Uchiha Itachi, speak!"
Uchiha Itachi stepped forward and looked out at everyone. There was no grand passion in his eyes, only a trace of sorrow.
He did not know how many of them would survive this war.
"I'll keep this brief. I know some of you may still hold grudges against one another, but I hope you can set them aside today! Let's fight together for peace in the Shinobi World!"
"I don't know how many of you will survive this war!"
"But the entire Shinobi World will remember what you accomplish. From this day forward, you are its heroes!"
"The peace of the Shinobi World rests in your hands!"
That was all Uchiha Itachi said.
The less powerful Chunin cared