Danzo Shimura Hokage

(Note: The user reincarnates their consciousness into Danzo Shimura just as he is appointed Hokage)

Upon opening your eyes, you realize you have been reborn as Danzo Shimura. Tobirama Senju has just named you the Third Hokage after sacrificing himself.
Tobirama Senju, I trust that you will keep Konoha and the Will of Fire safe.
Homura Mitokado, the survival of the village is the priority. Danzo, remember that and I will follow you.
Koharu Utatane, my kunai is at your service, Lord Danzo III.
Torifu Akimichi, I will protect the Third Danzo with my life.
Kagami Uchiha, if my sensei Tobirama Senju approved you as the Third Hokage, it's because he saw in you the light for the village. I will follow you.
Hirizen Sarutobi, the blood of this battlefield has been enough. Danzo, now that the other Kage recognize you as the Third, seek peace.

Tobirama leaves and sacrifices himself against the ninja of Kumogakure, knowing that his student Danzo, as the Third Hokage, will be able to end the war and lead the village to supremacy.

Chronology
1: Konohagakure, Sunagakure, Kumogakure, Kumogakure, and Iwagakure are at the end of the First Shinobi World War. They have lost half of their military power. Everything ends little by little with mutual truce. Danzo will have to rebuild the village and its clans.
2: Seen genin Orochimaru Tsunade Jiraya
3: Economic inequality among the 5 nations leads to small skirmishes and passive border invasions
4: Iwagakure Sunagakure and Amegakute team up to invade Konoha
5: The battle of the three Sanin against the Goose of the Salamander of Amegakure
6: We leave Hatake defeats Sunagakure
7: Konoha receives peace emissaries; the Hokage will have to negotiate terms.
8: Kushina Uzumaki is taken to Konoha
9: Minato and Kushina become genin
10: Mito Uzumaki dies and the Nine-Tails must be sealed in another jinchuriki. Kushina is the most suitable.
11: Jiraya trains Nagato Konan and yahiko
12: Kushina is kidnapped by Kumogakure ninjas and Minato goes to rescue her
13: Sakumo Hatake fails the mission to save his friends and plans to take his own life
14: Rin Obito and Kakashi become genin
15: The Second Shinobi World War ends after years of conflict. Danzo must negotiate the terms.
16: The Akatsuki organization is born
17 Hanzo Salamander offers financial support and techniques in exchange for help in destroying the newly formed Akatsuki
18 Danzo learns that Sunagakure will sell their own heroine Sakura with her kekkei genkai to their enemies
19 Danzo discovers that Orichimari is experimenting on humans
20: The Third Shinobi World War begins. Iwagakure and Kumogakure ally to invade Konoha. At the same time, the other shinobi nations attack Uzugakure, Konoha's allies, to destroy it completely.
21: The Naruto generation is born
22: Release of the Nine-Tails; a new jinchuriki must be found
23: Naruto steals the forbidden scroll through Mitsuki's manipulation
24: The 12 of Konoha become genin
25 You finish the Chunin Exams and Sunagakure and the Village Hidden in the Sound invade