The current time in the Ninja Academy universe is Kongen Ato De (After the Origin). The planetary cycles of the Earth are for all intents and purposes identical to Earth's. As such, there is a 365-day Gregorian year (it's not called Gregorian, there was no Pope Gregory, let's not delve too deep here). What happened approximately 2100 years ago? This is when it was believed the God Tree was planted on our world[?].
Before Kongen Ato De was Kongen Mae Ni (Before the Origin). This is a time in history where not much is known, and thus the years count down towards the year 0, which is when the God Tree was believed to be birthed.
The seasons of the year are slightly abnormal from our year. Spring begins with the first day of the year, January 1st, and winter ends on the last day of the year, December 31st. Each season is approximately a three month length of time. For most intents and purposes you can ignore this, but just know that if we say "winter" of a year we always mean the end of the year.
| ~0 | - | Age of Myth. Gods said to walk the earth. Birth of the God Tree. | -- |
| ~1000 | - | The mythical progenitor Kaguya eats the fruit of the God Tree, becoming the first wielder of chakra on Earth. | -- |
| 1912; Summer | - | The Senju and Uchiha clans sign a truce. Soon after, they make a pact with the Land of Fire, founding Konohagakure and start the one hidden village per country system. | -- |
| 1913; Spring | - | Kirigakure no Sato, Sunagakure no Sato and Kumogakure no Sato are founded. | -- |
| 1913; Summer | - | Kusagakure no Sato and Iwagakure no Sato are founded. | -- |
| 1916; Winter | - | Yukigakure no Sato is founded. | -- |
| 1921; Spring | - | Amegakure no Sato is founded. | -- |
| 1921; Summer | - | The First Great Shinobi War begins. | -- |
| 1925; Fall | - | The Five Great Nations sign an armistice treaty, ending The First Great Shinobi War. | -- |
| 1948; Summer | - | The Second Great Shinobi War begins. | -- |
| 1954; Winter | - | The Second Great Shinobi War ends. | -- |
| 1957; Summer | - | The Third Great Shinobi World War begins. | -- |
| 1959; Summer | - | The Battle at Kannabi Bridge signals the end of the Third Great Shinobi World War. | -- |
| 1959; Fall | - | Namikaze Minato is elected Yondaime Hokage of Konoha. | -- |
| 1960; Fall | - | The Kyuubi attacks Konohagakure. The fox is defeated by the Fourth Hokage and sealed into Uzumaki Naruto, the Fourth Hokage's new-born son, at the cost of his life. | -- |
| 1963; Winter | - | Konohagakure and Kumogakure sign a treaty of alliance, ending a period of war. | -- |
| 1968; Fall | - | The Uchiha Clan is destroyed under order of Konogakure at the hand of Uchiha Itachi. | -- |
| 1969; Summer | - | Otogakure no Sato is founded. | -- |
| 1973; Summer | - | Otogakure attacks Konohagakure during the Chuunin Exams. The Third Hokage, Sarutobi Hiruzen, and the Fourth Kazekage, Rasa, both die in combat with Orochimaru. | -- |
| 1976; Fall | - | Konohagakure is destroyed by the hands of Nagato under the cover of the organization Akatsuki. | -- |
| 1977; Fall | - | The Fourth Great Shinobi World War occurs. The Ten-Tails is summoned and the Infinite Tsukuyomi is cast upon the world. Uzumaki Naruto and Uchiha Sasuke defeat the Ten-Tails, Akatsuki, and dispel the Infinite Tsukuyomi, resulting in a full victory for the Allied Shinobi Forces. | -- |
| 1979; Winter | - | A plot to drop the moon onto the Earth is foiled by the Allied Shinobi Forces. | -- |
2102; Spring |
- | Ninja Academy Role Play Begins | |
| 2104; Fall | - | Iwagakure no Sato is invaded and controlled by a group by the name of "Akatsuki", relation to the historical Akatsuki unconfirmed. | [?] |
| 2105; Summer | - | Iwagakure no Sato is freed of "Akatsuki" rule. | [?] |
| 2106; Summer | - | International Chuunin Exams in Kusagakure no Sato. | -- |
| 2107; Spring | - | The known world is invaded and conquered by the Kumogakure Empire in the most successful blitzkrieg attack known to history. | [?] |
| 2107; Spring | - | Kyoukage, Tomoshibi Mikomi, is killed in combat against Kumogakure no Sato. | -- |
| 2107; Summer | - | The Ninja Crime Investigation Agency (NCIA) is formed within the Kumogakure Empire. | [?] |
2107; Summer to 2109; Spring |
- | Two Year Time Skip in Role Play | |
| 2109; Spring | - | Otogakure no Sato fails in an attempt to free itself from the Empire; remaining resistance members are disbanded to other countries. | -- |
| 2109; Summer | - | Iwagakure no Sato is freed from the Empire. | [?] |
| 2109; Summer | - | Konohagakure no Sato fails in an attempt to free itself from the Empire; remaining resistance members are disbanded to other countries. | -- |
| 2109; Fall | - | Iwagakure no Sato is invaded by Yukigakure no Sato. Tsuchikage Hikado is killed by "Uchiha Madara", the invasion is unsuccessful. | [?] |
| 2109; Winter | - | Fang's NCIA Hunting Squad has vanished. Members scattered through different parts of the world. | -- |
| 2109; Winter | - | Gobi 'frees' Kusagakure no Sato from the Empire. | -- |
| 2109; Winter | - | Sunagakure no Sato is freed from the Empire. | -- |
| 2110; New Year | - | Kirigakure no Sato is freed from the Empire. | -- |
| 2110; Spring | - | Battle of Nigiyakashufu resulting in the fall of the Kumogakure Empire and the NCIA. Death of Raikage, Inabikari Raikou. | -- |
| 2110; Spring | - | The Momochi Rakurai Explosion, a nuclear detonation, takes place in the Northern Sea during the battle of Nigiyakashufu. | [?] |
| 2110; Spring | - | Otogakure no Sato is freed from remaining NCIA rule. Death of Urseial Li. | -- |
| 2110; Spring | - | Kirigakure no Sato's First (and only) G.E.R.T. exam takes place. | [?] |
| 2110; Summer | - | Iwagakure Air Federation is founded. | [?] |
2110; Summer |
- | Five Year Time Skip in Role Play Begins | |
| 2113; Fall | - | Tsuchi Yuki Border Agreement of 2113 is signed by Earth and Snow Countries. | [?] |
| 2114; Spring | - | The Western Earth Invasion happens in the Country of Earth. | [?] |
| 2114; Fall | - | Tsuchi Yuki Aggression Declaration is made by the leaders of the Country of Earth. | [?] |
2115; Summer |
- | Five Year Time Skip in Role Play Ends | |
| 2115; Summer | - | Kirigakure Civil War | [?] |
| 2115; Fall | - | International Chuunin Exams in Metropolis | [?] |
| 2115; Fall | - | Destruction of Kusagakure no Sato | [?] |
| 2115; Fall | - | Iwagakure-Yukigakure War Begins | [?] |
| 2115; Winter | - | Arrakis Ninja Arts Tournament | [?] |
| 2115; Winter | - | Iwagakure-Yukigakure War Ends | [?] |
| 2116; Spring | - | Rai no Kuni Chuunin Exams | -- |