Why did Itachi slaughter his whole clan?

Itachi killed his clan because he was under the impression they were going to overthrow the village. Danzo struck a deal with Itachi that allowed Sasuke to be spared, so long as Itachi made it seem that he simply went rogue to test his power.

Why was fugaku planning a coup?

Following the Nine-Tailed Demon Fox’s Attack, Konohagakure’s leadership began to suspect that the Uchiha were behind the attack due to the Sharingan’s ability to control the beast. As such, the Uchiha — led by Fugaku Uchiha — began planning a coup d’état to overthrow the Konoha leadership.

What did Itachi do to Fugaku’s parents?

During the Uchiha Clan Downfall, Fugaku quickly realised Itachi was behind this attack and confronted him via a clone, expressing their respective views. Itachi then confronted his parents, but Fugaku and Mikoto did not resist and told Itachi that they were still proud of him and to promise to take care of Sasuke before they let Itachi kill them.

Why did Itachi become a spy for the Uchiha clan?

Despite this, the villagers still admired Fugaku and the Uchiha Clan’s efforts of maintaining peace. This did not stop Fugaku from conspiring a coup d’état that would allow the Uchiha clan to take control of the village out of spite. Eventually, Fugaku placed Itachi as a spy in the Anbu to pass information back to the clan.

Why did Fugaku kill his own clan?

Clan head Fugaku Uchiha planned to shake things up by staging a coup against the village’s authority. When word reached the village elders, the clan’s strongest young member was faced with an almost unthinkable choice: kill out his own clan for the sake of Konoha, or perish with them.

What happened to Sasuke’s father Fugaku?

As Itachi was his successor as head of the clan, Fugaku spent much of his time focusing on the development of his eldest and little time with his youngest. Sasuke trained constantly in order to get his father’s attention and approval. Near the end of his life, Fugaku had switched his attention to Sasuke, having lost hope in the wayward Itachi.

https://www.youtube.com/watch?v=ktDP5LzcqfM