Timeline

The following is a list of events as they take place in the world of the Overlord series, starting from the past and heading toward the present storyline.

Chronological Order of Overlord

 * 1) Blu-ray BOX4 Special Story: Overlord Prologue (Former Part)
 * 2) Blu-ray BOX6 Special Story: Overlord Prologue (Latter Part)
 * 3) Light Novel Vol.01: The Undead King
 * 4) Blu-ray BOX1 Special Short Story: Emissary of the King
 * 5) Blu-ray BOX2 Special Drama CD (#3)
 * 6) Blu-ray BOX1 Special Manga Supplementary Short Story: Drama of the Three Ladies
 * 7) Overlord Volume 10 Side Story
 * 8) Light Novel Vol.02: The Dark Warrior
 * 9) Light Novel Vol.03: The Bloody Valkyrie
 * 10) Light Novel Vol.04 Special Drama CD (#1): The Sealed Evil Tree
 * 11) Light Novel Vol.04: The Lizard Man Heroes
 * 12) Blu-ray BOX3 Special Drama CD (#4)
 * 13) Light Novel Vol.08: The Two Leaders
 * 14) Light Novel Vol.06 Special Drama CD (#2): The Dark Hero's Story
 * 15) Light Novel Vol.06 Special Drama CD (#2): The Maid Tea Party
 * 16) Light Novel Vol.05: The Men in the Kingdom (Part 1)
 * 17) Light Novel Vol.06: The Men in the Kingdom (Part 2)
 * 18) Light Novel Vol.07: The Invaders of the Large Tomb
 * 19) Light Novel Vol.09: The Magic Caster of Destroy
 * 20) Light Novel Vol.10: The Ruler of Conspiracy
 * 21) Overlord Compilation Movie 01 Bonus: The Pleiades Day
 * 22) Light Novel Vol.11: The Craftsman of Dwarf
 * 23) Light Novel Vol.12: The Paladin of the Holy Kingdom

2118 (20 Years Ago)

 * The Arcology War broke out in Europe and the Neo Nazi's Uniform became a hot topic.

2126 (12 Years Ago)

 * YGGDRASIL game service started.

YGGDRASIL Era

 * Touch Me became the World Champion of Álfheimr.
 * Touch Me saved Momonga from PKers, who were hunting down Heteromorphic players.
 * The Formation of the First Nine known as the Nine's Own Goal.
 * The Dissolution of the Nine's Own Goal and the Formation of Ainz Ooal Gown.
 * Ainz Ooal Gown conquered the Great Tomb of Nazarick and it became its guild headquarters.

2138 (Starting Point)

 * The Termination of YGGDRASIL.
 * Momonga and his guild base were transported to the New World.

~600 Years Ago

 * The Age of the Dragon Lords, the original lords of the New World, who ruled through the use of Wild Magic.
 * The Six Great Gods appeared and introduced Tier Magic to the New World.
 * The Slane Theocracy was founded in worship of the Six Great Gods.

~500 Years Ago

 * The Eight Greed Kings appeared and conquered the New World, spreading the influence of Rank Magic and leading to the decline of Wild Magic.
 * All Out War between the Eight Greed Kings and the Dragon Lords.
 * The Age of the Dragon Lords came to an end.
 * The internal conflict of the Eight Greed Kings, which led to their demise.

~300 Years Ago

 * The Downfall of Gatenbarg after the Civil War.
 * The Deep Darkness Dragon Lord encountered and defeated a Player.

~250 Years Ago

 * Evileye was born.
 * Fluder Paradyne was born.

~200 Years Ago

 * Rigrit Bers Caurau was born.
 * Hamsuke was born.
 * Zy'tl Q'ae appeared in the Great Forest of Tob.
 * The Evil Deities emerged and rampaged in the New World, causing unparalleled chaos and destruction.
 * The Thirteen Heroes were formed to combat the Evil Deities. The heroes defeated each Demon God and were eventually immortalized as heroes.
 * The Minotaur Sage appeared and began preaching strange revolutionary ideas.
 * The leader of the Thirteen Heroes killed his fellow player and refused to be revived.
 * Nations such as the Re-Estize Kingdom, Baharuth Empire, Dragon Kingdom and the Roble Holy Kingdom were founded.
 * The Adventurer's Guild was established after the Thirteen Heroes defeated the Demon God.

60 Years Ago

 * Ramposa III was born.

39 Years Ago

 * The reign of King Ramposa III began.

30 Years Ago

 * A group consisting of an adamantite adventurer team led by Vesture Kloff Di Laufen and two mythril adventurer teams collected a rare herb from Zy'tl Q'ae in the Great Forest of Tob.

25 Years Ago

 * Calca Bessarez was born.

22 Years Ago

 * Jircniv Rune Farlord El Nix was born.

20 Years Ago

 * Zuranon occupied a ruin and conducted horrifying experiments, which led to catastrophic results.
 * A city south of the Baharuth Empire was destroyed by a dragon.

19 Years Ago

 * Lakyus Alvein Dale Aindra was born.

16 Years Ago

 * Enri Emmot was born.
 * Renner Theiere Chardelon Ryle Vaiself was born.

10 Years Ago

 * Nemu Emmot was born.
 * Jircniv Rune Farlord El Nix was crowned Emperor of the Baharuth Empire. Using his new authority, he commanded the imperial knights to purge the imperial nobles in the capital.
 * Osk encountered Go Gin at the Empire's frontier.
 * Go Gin became the Martial Lord and champion of the Imperial Arena.
 * Calca Bessarez was crowned Holy Queen of the Roble Holy Kingdom becoming the first female monarch in the Holy Kingdom's history which resulted in a strained relationship between the north and south.

5 Years Ago

 * Fluder Paradyne and his disciples captured a Death Knight and transported it to Arwintar. It was imprisoned deep within the vaults of the Ministry of Magic for further research.
 * Under the leadership of Khajiit Dale Badantel, Zuranon infiltrated the fortress city of E-Rantel and prepared for the 'Spiral of Death' ritual.

Transition 1st Day

 * Momonga and the Great Tomb of Nazarick were transported to the New World.
 * Momonga held an emergency meeting with the Floor Guardians on the 6th Floor.

Transition 3rd Day

 * Momonga went outside of Nazarick along with Demiurge to see the new world.
 * Momonga jokingly suggested on taking over the world which Demiurge misinterpreted as his intention.

Transition 4th Day

 * The attack on Carne Village by the knights of the Slane Theocracy disguised as Imperial Knights from the Baharuth Empire.
 * Momonga intervened and rescued both the village and Gazef Stronoff. He established the name Ainz Ooal Gown and made it his mission to understand this new world and seek out any of his fellow guildmates.
 * Enri received two Horn of the Goblin General from Ainz Ooal Gown to protect herself, and used the first horn to summon a Goblin Troop.

Transition 8th Day

 * Shalltear Bloodfallen reported to Ainz before she left and joined with Sebas Tian and Solution Epsilon on their mission.

Transition 9th Day

 * Ainz and Narberal Gamma infiltrated the fortress city of E-Rantel as copper class adventurers under the alias of Momon and Nabe.
 * Lizzie Bareare appraised the compensated potion that Brita received from Momon and instigated her grandson to investigate him.

Transition 10th Day

 * Momon and Nabe met Swords of Darkness and agreed to jointly escort Nfirea Bareare to Carne Village.
 * After the party got attacked by a group of goblins and ogres, they stayed the night outdoors.
 * Clementine brought the Crown of Wisdom to Khajiit Dale Badantel.

Transition 11th Day

 * The Swords of Darkness and company arrived at Carne Village.
 * Nfirea revealed to Momon that he knew that he was actually Ainz Ooal Gown and seeked to learn the secret of the red potion from him.
 * Momon tamed the Wise King of the Forest in the southern part of Tob Forest.
 * Zach on his way to the Death Spreading Brigade-branch bumped into Clementine on her way to the workers which she engaged, and returned to the cemetery she also assailed Khajiit.
 * Sebas and Solution left E-Rantel and headed to the Royal Capital.
 * Shalltear encountered the Death Spreading Brigade and Brain Unglaus. She soundlessly defeated them while Brain escaped.
 * An adventurer team on patrol encountered Shalltear and got slaughtered, with only Brita left alive.
 * Shalltear encountered and engaged the Black Scripture but was summarily afflicted with an incomplete mind control spell.
 * The Adventurer's Guild received a message that a powerful vampire appeared at the Land of Karst.

Transition 12th Day

 * Momon, Nabe, Nfirea and the Swords of Darkness returned from Carne Village.
 * Clementine and Khajiit killed all members of Swords of Darkness and kidnapped Nfirea.
 * During the Cemetery Incident, Lizzie Bareare hired Momon and Nabe to rescue his grandson. Momon vanquished Clementine and Nabe defeated Khajiit in the E-Rantel Cemetery.

Transition 13th Day

 * The Adventurer's Guild promoted Momon and Nabe to mythril class adventurer.
 * Lizzie Bareare and Nfirea were relocated to Carne Village to fulfill the pact made with Ainz.
 * Ainz received a message from Albedo that Shalltear had rebelled against him.
 * E-Rantel authorities dispatched Momon in an emergency meeting regarding a powerful vampire.
 * Ainz Ooal Gown battled against Shalltear Bloodfallen and succeeded in killing her. The resurrection afterwards annulled the mind-control.

Transition 14th Day

 * The Adventurer's Guild promoted Momon and Nabe to adamantite class adventurer after the examination of the battle remnants against the vampire.

Transition 28th Day

 * Nazarick declares war on the Lizardmen tribes of the Great Lake.
 * Green Claw sends out Zaryusu Shasha to forge an alliance with Red Eye and Dragon Tusk.

Transition 29th Day

 * Zaryusu reaches Red Eye and meets Crusch Lulu, who agrees to the alliance.

Transition 30th Day

 * Zaryusu and Crusch journey together to Dragon Tusk and encounter Zenberu Gugu. After a duel between the two warriors, the tribe joins the alliance.

Transition 31st Day

 * The five lizardmen tribes gather at Green Claw Village and begin stockpiling and fortifying their position.
 * The tribes unite to form the Lizardmen Alliance.

Transition 35th Day

 * The Lizardmen Alliance wage war against the undead army of Nazarick and are victorious.

Transition 36th Day

 * Cocytus requested Ainz to spare the lizardmen and Ainz agrees to make them subordinates.
 * An army of undead led by Ainz and the Floor Guardians arrives at the Lizardmen Settlement.
 * Ainz meets Shasuryu and Zaryusu, and tells them to prepare their forces to fight Cocytus tomorrow.

Transition 37th Day

 * Cocytus fights and kills all of the Lizardmen who faced him.
 * The Lizardmen Alliance agree to become Nazarick's servants.
 * Crusch Lulu agrees to spy on the Lizardmen in exchange for Zaryusu's resurrection.
 * Zaryusu is resurrected by Ainz in front of all the Lizardmen, who now see the latter as a deity.

Trivia

 * The main storyline of Overlord series is set in the New World's timeline.
 * Since Overlord Twitter Side Story is non-canon, the timeline for it is not included.