354 A.D.
The Great Wars end. After a century of warfare, across four star systems and three dozen planets, over 20 billion Vulcans are killed. Large scale fusion, biological, and psionic weapons are used. This is the most savage war ever recorded that the warring species actually survived. Not even the Klingons have matched this level of destruction during a civil war.

355 A.D.
The Time of Awakening. With over 95% of the Vulcan population killed during the wars, the great philosopher Surak meets with leaders of all sides. Together they form a democratic coalition government founded on peace and understanding. The Vulcan philosophy of logic emerged gradually from these negotiations.

360 A.D.
The philosophy of Logic is formally published by Surak. Within a year almost half the Vulcan population attempts to adopt these principles. Most of the rest are sympatetic to Logic and adopt some of it's ideals. Only a small percent of the population are totally opposed to the pacifist Logic philosophy, they decide to leave Vulcan and settle a new world.

369 A.D.
The Exodus. Three giant interstellar cargo ships, refitted as colony ships, leave Vulcan with over 6000 dissident Vulcans. Turning their backs on the philosophy of Logic, they vow to uphold the traditional Vulcan ways. Unfortunately none of the telepathic masters leave with the Exodus, having all been killed in the wars or siding with Surak. This lack of telepathic skill leads to atrophy of mind skills. Some rumors hold that the legendary Stone of Gol was broken into parts, one held on each ship, but this was never confirmed.

377 A.D.
The Landing. The three colony ships settle on twin worlds. The contents of the cargo bays are used to build a city. The colony ships are canniballized to provide planetary defenses and a set of small defense ships.

386 A.D.
In the chaos of the settlement, a single warlord rises to power through political dealings and shrewd manipulation. By 388 A.D. he has established a power base and is the de-facto leader of the colonists. His name is Admiral Romulus.

395 A.D.
Under the leadership of Admiral Romulus, an Empire is officially declared. The Imperial Senate is convened, and the proconsuls are summoned. It culminates in the coronation of Emperor Romulus the First.

399 A.D.
Without proper maintenance or spare parts, two of the warp ships are rendered inoperable. The last ship is drydocked to prevent further decay.

417 A.D.
A fleet of small exploration ships begin to establish outposts on all planets in the Romulus System.

435 A.D.
Emperor Romulus dies unexpectedly. The Empire and the Homeworld are named in his memory.

440 A.D.
The Empire has spread throughout the Romulus system. Slow sublight probe ships begin to explore nearby ships, as the last warp ship is brought out of drydock and refitted.

446 A.D.
The refit of the last warp ship is complete. However as a crew is being trained, dissent breaks out over the use of the ship. A significant number of political dissidents demand to use the ship to leave the Empire.

450 A.D.
The moderates in the Empire decide that the Romulan Star Empire is too violent and extremist. Calling themselves the Debrune, they fight over the last intact warp ship. Eventually they steal the ship and settle four systems. It is believed that they took the Stone of Gol with them to prevent it's misuse.

462 A.D.
Geological prospecting reveals that there are no subspace-active materials in the Romulus system. Long range scans by probe ships show that nearby systems. The Empire begins to expand using ancient sublight colonization techniques, which will take centuries.

1542 A.D.
Romulan sublight ships find limited amounts of subspace active materials. Within 10 years a small handful of warp capiable ships are built. The Empire develops a unique style of transport, large carrier ships convey up to one thousand in their hulls and even entire vessles within their warp fields. This system works safely for centuries.

1943 A.D.
War breaks out between the Romulans and Vulcans when a Romulan scout ship believes himself to be under attack. A nearby Vulcan outpost is misinterpreted to be the aggressor, and hostilites escalate rapidly.

1945 A.D.
Vulcan scout ships begin covert observation of Earth. Serious consideration is given to initiating first contact, however it is concluded that without warp drive or a world government, they are not ready for contact. Earth is declared a Vulcan protectorate and is defended against Romulan incursions over the next 40 years. Vulcan sociologists estimate that it may be as many as 200 years before Earth is ready for contact.

1995 A.D.
Romulan forces begin to withdraw from Vulcan space. Vulcan sociological missions still monitor and visit Earth. Vulcan experts estimate it will be still at least 150 years before they may warrant contact.

2044 A.D.
The Romulan-Vulcan war comes to an end, with the Romulans pushed back beyond Tau Ceti.

2063 A.D.
A routine Vulcan survey ship detects a warp signature near Earth. Investiating it finds that the native have developed Warp technology over 80 years before expected. While initial contact is difficult, a tenative alliance between the Vulcans and Terrans is created. The Romulans see this as a military threat.

2150 A.D.
Earth exploration ships reach Romulus system. A botched first contact leads to destruction of the Earth expedition. The Romulans, believing this to be the first wave of an invasion, begin to construct a massive fleet.

2154 A.D.
In preparation for an anticipated Earth invasion, the Romulans complete a fleet of over 100 ships. Having determined the origin of the ships from salvaged computer systems, they head for Earth. The Earth-Romulan war begins with attack on Station Salem One, in orbit of Tau Ceti.

2160 A.D.
After six years of war, Earth is almost defeated. Most of the Earth fleet is destroyed. While attack ships begin to invade Earth and Mars, surviving forces mount a desperate last attack on the Romulan flagship in orbit of Charon, the only moon of Sol's outermost planet. Hopelessly outnumbered and outgunned, Earth forces win a miraculous victory and drive all Romulan forces back. A treaty is negotiated over subspace radio, establishing a 1 LY wide neutral zone between Earth and Romulan Space.

2161 A.D.
The United Federation of Planets is formed. An alliance of several worlds adjoining Romulan space, including Earth and Vulcan. Originally formed as a military and trade alliance, it quickly grows to be an interstellar organization equalling the Romulan Star Empire.

2265 A.D.
A prototype cloaking device is constructed. It is later fitted on a sublight attack ship.

2266 A.D.
A sublight Bird of Prey is dropped off by a warp carrier on the Federation side of the Neutral Zone, near Tau Ceti. Equipped with a cloaking device, it tests Federation defenses along the border. It is eventually destroyed by Federation defenses. This event also marks the first contact between the Romulans and the rest of the galaxy since the Earth-Romulan War

2267 A.D.
A tenative military alliance is forged between the Klingons and the Romulans. In the alliance numerous D7 battlecruisers are shipped to Romulus in exchange for cloaking technology. The D7 ships give the Romulans independent warp flight, and allow them to find larger supplies of warp coil material.

2268 A.D.
The Federation Starship Enterprise steals a cloaking device from the Romulans. During the incident a Romulan Commander is also abducted.

2272 A.D.
Romulans lose to the Klingons the Klach D'kel Brakt system in one of many minor border skirmishes.

2273 A.D.
The Federation begins use of reverse-engineered cloaking devices on some Starfleet vessles.

2311 A.D.
The Tomed Incident. A cloaked Federation ship patrolling the Neutral zone responds to a distress call. The call was a misinterpreted training exercise. The Federation ship is exposed half a light years into the Romulan Empire, however attempts at negotiation fail. Transmitting a distress call, 5 more ships arrive as reenforcements. After a long and brutal battle, a stalemate is achieved as both sides are equally damaged. In the aftermath, negotiations prevent war, but in the resulting Treaty of Algeron the Federation was banned from using or posessing cloaking devices, in exchange the Romulans surrendered Galornadon Core and the Tomed system. After this incident, the Romulans withdraw all diplomatic represenatives from across the galaxy, and withdraw from the galactic scene.

2342 A.D.
Conditions deteriorate between the Klingon and Romulan empires, leading to a limited but violent border war.

2344 A.D.
The Federation Starship Enterprise-C intervenes in the Klingon-Romulan war by defending Narendra from a Romulan attack. This leads to a stronger alliance between the Klingons and the Federation, but further estranges the Federation and the Romulans

2346 A.D.
The Klingon-Romulan war reaches a new level during the Romulan attack on the Klingon base at Khitomer. After this battle, the Klingons reenforced their claim on Mempa sector.

2347 A.D.
An uneasy peace treaty is reached in the Klingon-Romulan war. No gains are made and both sides agree to the prewar borders.

2364 A.D.
The Romulans decide to re-enter the galactic stage, they send one of the new D'Deridex Warbirds to the Federation edge of the Neutral Zone, where they declare their intent to participate in interstellar affairs.

2367 A.D.
The Romulan Star Empire begins to secretly supply weapons to Kriosian rebels fighting against the Klingons. At the same time, the Romulans are also secretly providing the House of Duras with weapons and supplies.

2368 A.D.
Romulan influence in the Klingon civil war is discovered by both the Federation and the Klingon faction lead by Gowron. Romulan forces are repulsed.

2371 A.D.
The Tal Shiar of the Romulan Star Empire forges a secret alliance with the Obsidian Order of the Cardassian union. Together they secretly build a total of 40 ships. The entire fleet is destroyed during their attack on the Founder's Homeworld. In an utter failure, every last ship was destroyed and in the aftermath the Tal Shiar found itself lacking ships and experienced operatives and it's influence has waned since.

2373 A.D.
Romulan forces forge an uneasy alliance with the Klingons and the Federation to fight the Dominion threat. 7 D'Deridex warbirds are immediately dispatched to join the combined fleet.

The above information was provided by Memory Alpha Movement.