Nine-Tailed Demon Fox's Attack

Twelve years before the start of the series, after the end of the Third Great Shinobi World War, the Nine-Tailed Demon Fox attacked the village of Konohagakure.

The attack coincided with Kushina Uzumaki, the second jinchūriki of the Nine-Tails, giving birth to Naruto. It was mentioned that the jinchūriki's seal was at its weakest when giving birth, thus, it was carried out in secret, with Biwako Sarutobi, the Third Hokage's wife, as her midwife, a few ANBU as security, and with Minato keeping the Four Symbols Seal holding the Nine-Tails secure. The location was eventually discovered by Madara Uchiha, killing the ANBU and Biwako, and holding the newborn Naruto hostage. While holding Naruto at knife point, Madara ordered Minato to walk away from Kushina. Minato tried to negotiate with Madara, as the seal began to weaken. Kushina pleaded with Minato to protect Naruto. It was at this moment that Madara attempted to stab Naruto. Before the knife could hit Naruto, Minato was able to snatch Naruto away from Madara. But to his surprise Naruto's baby clothes were filled with exploding tags, forcing him to use the Flying Thunder God Technique and transport himself and Naruto away from the explosion but also away from Kushina.

With Minato away from Kushina, Madara used a technique to extracted the Nine-Tails from Kushina. He hurried the extraction as he noted that the seal holding the Nine-Tails also had carried the Flying Thunder God technique seal, so Minato would not be far behind him in trying to rescue Kushina. Using his Sharingan, he gained control of the Nine-Tails, directing it towards Konoha to destroy the village. However, even at having already had a tailed beast extracted from her, Kushina was still alive and struggled to speak. Madara directed the Nine-Tails to crush her but was rescued in the nick of time from being crushed by the large paws of the Nine-Tails by the arriving Minato. They soon escaped back to Naruto's secret location where he set Kushina beside Naruto before heading off to protect the village of Konoha.

The Nine-Tails' strength at this point was so great, that even far away from the village, a young Itachi Uchiha was able to sense its presense.

Nobody was able to stop the Nine-Tails until Minato Namikaze, the Fourth Hokage, arrived to apply the seal on the Nine-Tails and sealed the Yang portion of the Nine-Tails' chakra into his newborn son, Naruto Uzumaki while keeping the Yin portion within the Death God. Kushina's involvement in the sealing process is yet to be seen, as she seemingly had contributed her chakra and soul into the sealing of the Nine-Tails into Naruto. The village suffered heavy casualties during the attack, such that few of the villagers would forgive Naruto (who they viewed as the fox) for its actions despite the fact that he was the one who contained the beast.

Though the Nine-Tails had attacked many settlements regularly throughout history for no apparent reason, Jiraiya, Minato Namikaze, and Itachi Uchiha speculate that Madara Uchiha was behind the attack on Konoha. Madara denies this and attributes its rampage as a natural occurence: however, Minato claims to have fought him on the night of the attack.

As the Uchiha clan's Sharingan is able control the Nine-Tails, the elders of the village suspected them of being responsible of unleashing the attack. It was this spite that led them to attempt a rebellion, which ended with their mass assassination before it could happen.

In the anime, the Nine-Tails is revealed to have left behind large amounts of its chakra during the attack that, when gathered by Kazuma, allowing him to turn Sora into a pseudo-jinchūriki.