This timeline attempts to cover the major events leading up to and during the seven-season run of the television show Star Trek: Deep Space Nine. It is contributed to the database in the hopes that it will spark interest in watching the show, which in the author's personal opinion, is simply the best incarnation of Star Trek.
The series tended to eschew the traditional method of using stardates to denote the passage of time, and as such, the timeline will be presented in linear fashion using conventional dating methods to denote when any particular event took place.
Deep Space Nine
Star Trek Timeline
The Star Trek Project
Be warned, there be spoilers below. In great quantity.
The Distant Past
The remote Alpha Quadrant planet, Bajor, over the course of ten thousand years, is visited by nine strange devices called Orbs. These Orbs grant the Bajorans visions of an often prophetic nature, and the Bajorans begin to believe the Orbs are sent to them by gods named "The Prophets". The Bajorans create a religion around these gods and call the Orbs "Tears of the Prophets".
The Cardassian Union invades and conquers Bajor, stripping the planet of all natural resources and enslaving the Bajoran population. They also steal eight of the nine Orbs for scientific research. The ninth Orb, The Orb of Prophecy and Change is hidden from the Cardassians by Bajor's religious leaders.
Benjamin Sisko is born to Sarah and Joseph Sisko. However, unbeknownst to anyone, Sarah Sisko is actually a host for a Prophet in human guise, creating the exact circumstances necessary for Benjamin to be born for as-yet-unknown reasons.
A new lifeform, made of a viscous fluid, is discovered in Bajor's Denorios Belt. It is given over to a Bajoran doctor for study by the Cardassians, where it is discovered that the lifeform is sentient and can alter its shape at will. It soon adopts the name Odo, which is a bastardization of the Cardassian word meaning "unknown sample".
The Cardassians begin construction of space station Terok Nor in orbit of Bajor. It becomes the symbol and seat of Cardassian power in the Bajoran system, as well as an orbital mining facility. It is overseen by the Cardassian prefect of the Bajoran sector, Gul Dukat.
A Bajoran woman named Kira Meru catches the fancy of Gul Dukat, and in exchange for a guarantee for her family's safety, Kira agrees to become Dukat's comfort woman.
Fearing that their son will suffer due to a severe learning disability, Richard and Amsha Bashir subject their young son Jules to genetic therapy and enhancement that is classified as illegal by The United Federation of Planets. Jules later changes his name to Julian and manages to keep his altered state secret from the government for many years.
Starfleet ensign Benjamin Sisko meets a joined Trill named Curzon Dax for the first time at Pelios Station. They become fast friends, their friendship lasting many years and through many host bodies for the Dax symbiont.
On Bajor, the daughter of Kira Meru, Kira Nerys, joins the Shakaar resistance cell at the age of twelve in order to fight the Cardassian occupation of Bajor.
After serving eight years as a cook on a Ferengi freighter, Quark opens up a bar on the Promenade of Terok Nor, enlisting family members Nog and Rom to work on his staff.
Odo arrives at Terok Nor, having rebelled against being an object of scientific study. He assumes humanoid form and becomes an abritrator of disputes amongst the Bajoran slaves on the station. He comes to the attention of Gul Dukat, who pressures Odo into assuming responsibility for investigating a murder on the station. During this investigation, he meets resistance fighter Kira Nerys for the first time. Dukat later in the year makes Odo his chief of station security, replacing a Cardassian named Thrax.
The Battle of Wolf 359 takes place between a single Borg vessel and an armada of Federation battleships, the USS Saratoga amongst them. Onboard Saratoga is Benjamin Sisko, serving as the ship's first officer and with him are his wife Jennifer Sisko and his son Jake Sisko. Jennifer is killed during the battle, though Ben and Jake are numbered amongst the battle's few survivors.
Benjamin Sisko, obsessed with obtaining vengeance against the Borg, accepts a position at Utopia Planitia shipyards in orbit of Mars to begin work on a new type of starship designed specifically to defeat the Borg.
Curzon Dax, the seventh host body for the Dax symbiont, dies on the pleasure planet Risa during a ritual called "jamaharon". The symbiont is transferred to its new host, a young woman named Jadzia.
2369 (First Season)
The Cardassian Union, facing military pressure from Bajoran resistance groups and political pressures both internal and external, withdraw from the Bajoran sector, returning control of the planet and local space to the Bajoran people.
The Bajorans immediately form a provisional government and an armed militia force. They also apply for membership in the United Federation of Planets, inviting Starfleet to administer Terok Nor as a Federation starbase. The station will field a mixture of both Bajoran and Starfleet officers, and is re-christened Deep Space Nine.
Cardassian spy Elim Garak is disgraced and sentenced to exile on Deep Space Nine, the only Cardassian to remain in Bajoran space following the withdrawal. While Garak finds gainful employment on the station as a tailor, he is looked upon with suspicion by both Bajoran and Starfleet personnel.
Sisko is promoted to commanding officer of Deep Space Nine. Kira Nerys, promoted to the rank of Major, reluctantly agrees to serve as his first officer. Lieutentant Jadzia Dax is brought aboard to serve as the station's science officer. Julian Bashir, now a doctor is assigned as the station's chief medical officer, while former Enterprise transporter chief Miles O'Brien is made the station's chief of operations. Odo stays on board the station as head of security.
Sisko meets Kai Opaka, the spiritual leader of Bajor. She tells Sisko that he is destined to become Bajor's emissary to The Prophets, and that he will discover something known as The Celestial Temple, and open its gates. As a gesture of goodwill and faith, Opaka gives him the last Orb in Bajoran possession: the Orb of Prophecy and Change. Sisko returns to the station with the Orb (after having a vision given to him by it) and asks Dax to analyze it to determine its origins.
Dax discovers that most of the Orbs were discovered in one specific region of Bajoran space, and she and Sisko take a runabout-class starship to investigate. They there discover the galaxy's only known stable wormhole, connecting the Alpha Quadrant of the galaxy to the Gamma Quadrant. This wormhole is discovered to have been constructed by noncoporeal alien beings who live outside of linear time, able to see the past, present, and future with ease. The Orbs were sent out into normal space as probes by these beings as they searched for other signs of intelligent life. The beings can hardly accept that the majority of sentient life in the galaxy experiences time as linear.
When news of the discovery reaches Bajor, the populace believes that, indeed, Sisko has found the Celestial Temple and opened its gates, and is accepted by the Bajorans as the long-foretold Emissary to the Prophets. The beings within the wormhole are generally accepted to be The Prophets of the central Bajoran faith system.
Kai Opaka is killed on a planet in the Gamma Quadrant, opening the way for a new kai to be elected.
2370 (Second Season)
Bajoran Minister Jaro Essa and religious Vedek Winn Adami covertly conspire to overthrow the Bajoran provisional government and seize power, hoping to drive the Federation from Bajor. Their attempt fails, and while Jaro is disgraced, the more politically-savvy Winn emerges from the scandal largely unscathed.
Kira and Vedek Bareil Antos begin a romantic relationship.
Ferengi trade expeditions to the Gamma Quadrant bring back unconfirmed rumors of a mighty empire called The Dominion.
The United Federation of Planets and the Cardassian Union sign a peace treaty, a measure of which cedes some planets formerly under Federation jurisdiction to the Cardassians. A demilitarized zone is also created between the two powers. Many former Federation citizens resident on the ceded planets express their disappointment and resentment toward the Federation, but their pleas go unheeded.
The Cardassians begin hostilities towards those Federation residents still present in the DMZ. These colonists, now firmly convinced the Federation has abandoned them, arm themselves to resist the hostilities, calling themselves the Maquis. Most Federation citizens regard the Maquis not as freedom fighters but as terrorists.
Winn Adami, who came to political prominence during the unsuccesful coup earlier in the year, is elected kai and takes her place as the spiritual leader of Bajor.
Lieutenant Ro Laren, formerly of the USS Enterprise is assigned by Starfleet to covertly infiltrate the Maquis. Sympathizing with their cause, she abandons her Starfleet commission and joins the Maquis' resistance efforts against the Cardassians. In the months to follow, many other Starfleet officers will do the same.
The Dominion makes first contact with the UFP by detaining Sisko and Quark in the Gamma Quadrant. They are held captive by the Jem'Hadar, the genetically engineered super-soldiers of The Dominion.
Jem'Hadar battleships destroy the colony of New Bajor as well as Galaxy class starship USS Odyssey
2371 (Third Season)
Fearing further incursions by The Dominion in the Alpha Quadrant, the Federation assigns a prototype battleship named USS Defiant to Deep Space Nine to assist in the station's defense. The Romulan Star Empire donates one of their cloaking devices for use on Defiant, under the caveat that the device only be used in the Gamma Quadrant.
During largely unsuccessful attempts to negotiate peace with The Dominion, the Federation learns of The Dominion's ruling class, a race of shapeshifters that are called The Founders. Odo is a member of this race, and discovers that he was sent away from his home out into space while still an infant in order to learn about the various species in the galaxy.
Dr. Bashir discovers that the Jem'Hadar are genetically engineered to be dependent on an enzyme called ketracel white that the Jem'Hadar cannot synthesize naturally.
The Cardassian Union and Bajor sign a peace treaty largely negotiated by Vedek Bareil, who dies during the final negotiations in a shuttle accident.
Benjamin Sisko sponsors Nog's entrance into Starfleet Academy. Nog becomes the first Ferengi in history to enter the Academy.
Grand Nagus Zek, leader of the Ferengi, obtains the Orb of Wisdom from the Cardassians and returns it to the Bajorans.
Covert organizations within both the Cardassian and Romulan military structure plan and launch a preemptive strike upon the homeworld of the Founders, destroying it. However, the Founders had learned of the plan some time before, evacuated their homeworld, and actually encouraged the strike so that the Founders would have a reason to wipe out the combined Cardassian and Romulan fleets. This stunning defeat is a major setback for both powers.
Klingon general Martok, second in power within the Klingon government only to Chancellor Gowron is abducted during a hunting expedition and replaced by a Founder.
Jake introduces his father to Kasidy Yates, a freighter captain. Sisko and Yates begin a romantic relationship.
Former leader of the Shakaar resistance cell on Bajor, Shakaar Edon, is elected First Minister on Bajor, the highest political office on the planet.
Benjamin Sisko is promoted to captain.
Jadzia Dax is promoted to lieutenant commander.
Julian Bashir is promoted to full lieutenant (from lieutentant junior grade)
Odo kills a Founder impersonating a Federation ambassador in order to prevent him from starting a war between the Federation and the Tzenkethi. It is the first time in the history of the Founder race that one has harmed another.
The civilian based Detapa Council on Cardassia Prime overthrows the Cardassian militaristic government, the Cardassian Central Command.
2372 (Fourth Season)
The Founder impersonating General Martok convinces the Klingon Empire to invade the Cardassian Union. The Federation strongly objects, causing the Klingons to withdraw from the Khitomer Accords, effectively ending the long alliance between the two. The Klingons continue their hostilities toward the Cardassians, and to a lesser extent, the Federation, for more than a year.
Lieutenant Commander Worf, formerly of Enterprise, is assigned to Deep Space Nine as its strategic operations officer. He also assumes command of Defiant.
Federation Admiral Leyton attempts a coup d'etat within Starfleet, but is foiled at the last minute by Captain Sisko.
Assisting Sisko in his investigation of the coup attempt, Odo is unknowingly infected with a virus meant to kill all Founders. A covert group called Section 31 engineered and infected Odo with the virus.
Kasidy Yates is arrested for smuggling supplies to the Maquis. She is sentenced to six months in a Federation penal colony.
Odo is found guilty of murdering another Founder, and as punishment is stripped of his shapeshifting abilities by the other Founders. During his trial, he unknowingly infects the Founders' Great Link with the Section 31-engineered virus.
2373 (Fifth Season)
The Founder impersonating Klingon General Martok is exposed and killed at the Klingon military base Ty'Gokor.
Worf and Jadzia Dax become romantically linked.
The Cardassians return the Orb of Time to the people of Bajor.
Dr. Julian Bashir is abducted by The Dominion and is replaced with a Founder impersonator.
Kasidy Yates is released and returns to the space station.
Sisko begins experiencing visions of the lost Bajoran city of B'hala and is driven to unearth it. At the same time, he is given prophetic visions of utter disaster should Bajor join the Federation. At the last minute, Sisko convinces Kai Winn to delay Bajor's imminent entry.
An infant changeling is discovered near DS9 and given unto Odo's care. However, it dies, but Odo absorbs its remains. This somehow returns Odo's shapeshifting abilities to him.
The Cardassian Union officially joins The Dominion, with Gul Dukat assuming head of state duties for the Union. A massive fleet of Dominion ships enters the Alpha Quadrant, and the combined Jem'Hadar and Dominion fleets drive off the invading Klingons. Dukat then begins an effort to completely eliminate the Maquis, leaving few, if any, survivors.
The Founder impersonating Dr. Bashir is exposed while trying to destroy Bajor's sun and killed.
Worf and Garak rescue both Martok and Bashir from a Dominion internment camp. The Klingons reaffirm the Khitomer Accords as a result, and Martok becomes the Klingon liason officer to DS9.
Bashir's genetic enhancements are discovered, but his father accepts responsibility for the crime and is sentenced in his son's place.
The Dominion War begins in earnest. Dominion forces seize control of DS9 and put it under the joint command of the Vorta Weyoun and Dukat. All Federation and Allied forces vacate the Bajoran sector. At Sisko's urging, Bajor signs a pact of non-aggression with The Dominion, allowing Bajoran forces to remain on DS9 during The Dominion's occupation.
Kira, whom Odo has secretly loved for years, discovers his feelings for her. They become romantically involved shortly thereafter.
2374 (Sixth Season)
With the aid of an internal resistance led by Major Kira, Starfleet eventually re-takes DS9. Dukat is taken prisoner. Sisko insists that The Prophets keep further Dominon fleets from entering the wormhole. The Prophets acquiese to his demands, but warn that their help comes with a price.
Nog is given a field promotion to ensign.
Gul Damar, Dukat's primary aide-de-camp is promoted to legate and made the new leader of Cardassia under The Dominion.
Martok is made Supreme Commander of the Ninth Klingon Fleet assigned to protect the Alpha Quadrant.
Worf and Dax marry.
Dukat escapes from custody.
Section 31 attempts to recruit Bashir into their ranks due to his genetic enhancements. Bashir refuses, but Section 31 still considers him an operative.
Betazed is invaded and conquered by The Dominion.
Aided by Garak, Sisko connives to bring the Romulans from neutrality in the Dominion War to allying with the Federation and Klingon war efforts. This plot succeeds, though at a terrible price to Sisko's sense of morality.
Dukat discovers the Pah-Wraiths, beings similar in nature but opposed in belief to The Prophets, and allys himself with them. Using Dukat as a tool, the Pah-Wraiths seal the wormhole, killing Jadzia during the process. The Dax symbiont barely survives.
On route back to the Trill homeworld, the Dax symbiont takes a dramatic turn for the worse. It is implanted into the only Trill available and becomes Ezri Dax.
Kira is promoted to colonel.
2375 (Seventh Season)
Directed by a vision from The Prophets to the planet Tyree, Sisko discovers a new orb, the Orb of the Emissary. Through it, he learns that the entities in the wormhole were responsible for his birth. The Orb also re-opens the wormhole.
Ezri Dax becomes DS9's counselor.
The Founder's disease, engineered by Section 31, begins to manifest.
Ensign Nog loses a leg in the critical battle for AR-558. It is replaced with a biosynthetic one.
In order to subvert Kai Winn, Dukat has himself surgically altered to look like a Bajoran. He convinces her to abandon worship of The Prophets and take up worship of the Pah-Wraiths.
Sisko marries Kasidy Yates. They shortly thereafter conceive their first child.
The Breen ally with The Dominion.
Legate Damar rebels against The Dominion and forms a Cardassian-based resistance.
Sisko dispatches Odo, Kira, and Garak to Cardassia Prime to aid Damar's resistance efforts. Kira is given a Starfleet commission with a rank of commander.
Defiant is destroyed in battle at Chin'toka.
Odo begins to manifest symptoms of Founder's disease.
Worf challenges Chancellor Gowron's authority and kills him in honorable combat. He is given the mantle of leadership of the Klingon Empire, which he refuses, instead passing it to General Martok, who accepts and becomes the new head of state.
Bashir and O'Brien extract the cure for the Founder's disease from the mind of Section 31 operative Luther Sloan. Sloan commits suicide.
Bashir cures Odo.
Defiant-class starship USS Sao Paolo is assigned to DS9 and is re-christened to become the second starship Defiant.
Bashir and Ezri Dax begin a romantic relationship.
Grand Nagus Zek retires as leader of the Ferengi Alliance, appointing Rom his successor.
The Alpha Quadrant Alliance consisting of Federation, Romulan, Klingon, and rebelling Cardassian forces retake Cardassia Prime from Dominion and Breen forces. Before surrendering, the Dominion orders the complete genocide of the Cardassian race as punishment for their rebellion. They are stopped when Odo promises to give the Founders the cure for their disease, but nearly one billion Cardassians lose their lives.
Dukat and Winn attempt to release the Pah-Wraiths from their prison in the Fire Caves on Bajor. They are thwarted at the last minute by Sisko. Winn and Dukat are killed, and Sisko leaves his humanity behind to join the Prophets in the wormhole, though he promises Kasidy that he will return soon.
O'Brien and his family leave DS9 and return to Earth. Worf is made Federation ambassador to the Klingon Empire. Garak returns to Cardassia Prime to help in its recovery. Nog is promoted to lieutenant. Kira returns to command DS9, reassuming her Bajoran commission and rank of colonel.
Most information for this timeline adapted from information found in the Deep Space Nine Technical Manual, my own memory, and the book Avatar by S. D. Perry.