In the Two Hundred Twenty-Third year of the Fourth Era, the Last Dragonborn (who, it turned out, was not the last) officially declared war on the Aldmeri Dominion by razing the Thalmor Embassy in Skyrim to the ground on the Thirtieth of Frostfall. No one missed the symbolism.

At the same time, a massive rebellion, stirred up by the Nerevarine, erupted in Elsewyr. Within days, several cities are wrenched from the Thalmors' grasp.

A month later, the Dragonborn led a massive coalition of soldiers from Hammerfell, High Rock, Orsinium, Skyrim, and Morrowind in a drive through Cyrodiil to the Imperial City.

The Khajiit Revolution successfully removed all Thalmor presence from Elsewyr and reunited the province later that week.

After a surprisingly bloodless fortnight, the Army of the Dragon arrived at the gates of the City. They were met by Emperor Titus Mede II and a company of Penitus Oculatus. After a brief exchange of words, Titus gave the throne to the Dragonborn, who then changed his name to Dovahkaaz (Dragon Cat, in the dragon tongue).

A week after Cyrodiil's surrender, the Elsewyri forces, still under the leadership of the Nerevarine and with reinforcements from Argonia, launched an invasion of Valenwood. The Army of the Dragon marched in nine days later to reinforce the offensive which had ground down to a tree-by-tree slog. Even with that second front, the Thalmor still held three strong points two months into the Siege of Valenwood.

At that moment, reinforcements from the Summerset Isles arrived and the Thalmor counter-invasion began.

Their first eight boatloads of a hundred soldiers, each, landed in the vicinity of Anvil. Their rapid advance from their landing zones was met with determined resistance by the Anvil, Skingrad, and Kvatch chapters of the Fighters' Guild. Despite being outnumbered more than three to one, they contained the Thalmor for two weeks, long enough for half of the Army of the Dragon arrived and routed the elves.

A similar story played out on the shores of Hammerfell. When the Thalmor arrived, their ships came under attack from numerous privateer vessels. Two of the Altmer transports were sunk before they could offload their troops. The soldiers who landed were quickly beset by hundreds of Alik'r cavalrymen. The resulting battle lasted for nearly two hours, only ending as early as it did because of the destruction of the remaining Thalmor ships and subsequent bombardment of their warriors. They quickly surrendered.

The most brutal conflict of the entire War was the Elsewyr landing in Senchal. The elves arrived at an utterly deserted settlement. When the first soldier's boots hit the shore, the entire landing went to Oblivion. A legion of werelions rushed out from the surrounding swampy jungle and swarmed the landing zone. The slaughter lasted no more than twenty minutes. The lycanthropes even went as far as tearing the ships to flinders, leaving no survivors.

Thanks to a clever commander, the Thalmor were more successful in High Rock. Their fleet sailed along the coast toward Northpoint before doubling back and landing at Daggerfall. Because of the original course, only the Daggerfall town guard was available to dispute the Altmer landing, but they were quickly overwhelmed. With that foothold obtained, the High Elves fortified their position, waiting for reinforcements. Over the next four months, the Imperial Legion, with help from the various chapters of the Fighters' and, surreptitiously, Thieves' Guilds, assaulted Daggerfall three times, but they were driven back each time.

In the wake of the third assault, the reinforced Thalmor pushed up the peninsula, taking Camlorn in a week.

That was when the world learned that the dragons had chosen a side, that of Dovahkaaz. In simultaneous assaults, Odahviing led over a dozen dragons against the fleets that were meant to deliver the invasions of Skyrim and Morrowind while Paarthurnax brought nearly a hundred more to bear against the Thalmor in High Rock.

The attack on the fleets took place over a single night, with the dragons managing to surprise the elves. While the dragons refuse to divulge the details, what is known is that, come morning, the horizon glowed with the burning wrecks of ships, and there were no mortal survivors.

In the assaults of Daggerfall and Camlorn, with innocent bystanders involved, a more tactful and precise approach was used. No destructive Thu'ums were used; teeth and claws and blade-like tail-tips were wielded in their stead, usually following a use of the Thu'um to rip away their enemies' weapons. After twenty minutes, half a legion of Orsimer berserkers launched their own assault on each city. In the street-by-street combat that followed, everyone wearing Thalmor armor or robes was shown no mercy. With the death of the last Aldmeri soldier in Daggerfall, the Battle for High Rock ended.

The invasion of Argonia will likely become a textbook example of how to use the knowledge of the local environment to defeat a much superior force. The Altmers' landing went off without opposition or incident. It was as they started their advance into the swamp that complications arose. By the time the even caught sight of Argonian forces, half of their force was dead or incapacitated due to disease, wild animals, or hazardous terrain. The ensuing chase almost wiped out the Thalmor. When there were only twenty elves left out of four hundred, the lizards finally revealed their full strength, all fifty soldiers, led by a twenty-one-year-old Dragonborn named Shouts-At-Sun. They did not use a single arrow or spell to defeat the invaders, nor did they need to. The campaign, if it can be called that, lasted two and a half months.

Curiously, another fleet was sighted off the coast from Soulrest. Their planned landing areas will never be known, as all four ships disappeared in the Padomeic Ocean before they could come within sight of Tilmoth.

Back in Valenwood, the Armies of the Dragon and Elsewyr continued their drive to root the Thalmor out of mainland Tamriel, paying for every foot of ground they captured with many lives. By the thirteenth of Rain's Hand, 4E 224, only one strong point, Greenheart, had fallen to the Empire, with the other two under siege.

The sieges had little effect until the ninth of Second Seed, when the privateer flotilla blockaded the province and engaged the Thalmor supply ships. Falistene surrendered on the seventh of Midyear. Woodheart continued to hold out, much to the frustration of the Dragonborn and his allies. Finally, on the second of Last Seed, with the largest concentrated army seen in Tamriel to that point, the Empire launched its final assault on the city.

The Nerevarine and Dovahkaaz were each at the forefront of their respective armies as they charged the Aldmeri fortifications. Despite a hail of magic and arrows, both heroes reached the outer barricade intact. With a powerful, combined Unrelenting Force, they Shouted away every obstacle, though not every soldier, between them and the city in a twenty foot swath. The pair continued their charge, keeping most of the defenders' attention focused on them, allowing a number of their soldiers to reach the breach alive and able to fight.

Of what happened inside Woodheart, little is known. Only that, off the one thousand nine hundred seventy men and women who entered, five hundred eighty three, including the Dragonborn and Nerevarine, came back out. As of this writing, none of them have spoken about the assault other than to say that they killed every Thalmor in the city. The battle ended on the third.

Over the next year, the Empire rebuilt its army and navy while fending off Thalmor probes. Finally, on the twenty third of Midyear, 4E 225, the largest assembled fleet in Nirn's history set sail with eight hundred fifty ships and eighty five thousand soldiers. Following them were a hundred supply ships and eighty five medical vessels, enough support to keep the reconstituted Army of the Dragon fighting for up to a year.

A sixth of the fleet split off and assaulted the westernmost of the Summerset Isles, Auridon, while the rest continued on to Summerset.

The former part of the task force split into two prongs, both reaching their targets on the seventh of Sun's Height.

The southern prong, consisting the Companions and the Morrowind, Hammerfell, and High Rock branches of the Fighter's Guild, under the command of Aela the Huntress and her and Dovahkaaz's adopted children, Ma'isha and Ma'rahka, landed at Skywatch.

The northern prong, drawn from the Cyrodiil, Valenwood, Elsewyr, and Argonia branches of the guild and commanded by Modryn Oreyn, started their invasion at Firsthold.

The Summerset invasion fleet divided into three, striking at Lilandril, Shimmerene, and Dusk on the thirteenth. The battles that followed were drawn-out, bloody affairs.

Each of the landing zone cities fell within days of each other in Last Seed. Firsthold was captured on the third and Shimmerene on the fourth. Lilandril was next, becoming Imperial property on the ninth, followed by Dusk on the twelfth. Skywatch held out the longest, due to its mountainous location, finally falling on the nineteenth.

After a week fortifying their footholds, the Legions pushed forward. From Lilandril, Firsthold, and Skywatch, the Army drove southward. From Dusk and Shimmerene, they advanced to the East. Marbruk Brook, Karnwasten Moor, and Rosefield were taken a month later. That pattern continued for town after town.

After a year, Auridon was completely under Imperial control, the Lilandril front had advanced to Cloudrest, the Dusk front had reached Sunhold, and the Shimmerene front was on Alinor's doorstep at Riverwatch.

It was at Cloudrest that an unexpected behavior was first observed. When the Army of the dragon arrived, they found the city devoid of Thalmor. The citizens had revolted and pledged allegiance to the Empire. Across the northwestern quarter of Summerset, the revolt toppled Aldmeri counts again and again. The only settlement north and west of Ebon Stradmont where was combat was the Crystal Tower.

To the South was a much harder slog. There was no revolt to help there. While the advance from Dusk slowed down to a crawl, the central prong struck out from Riverwatch, surrounding Alinor and laying siege to the city.

Over the next eleven months, both sides fortified their positions, occasionally sending out forays to test each other's defenses. As the time passed, both forces began to run low on supplies. The Imperial army managed to receive periodic resupply when each of the other fronts arrived to reinforce the siege, but it still was not enough to keep the Army in peak condition.

As they were driven back, the Thalmor had grabbed all the food they could and put the rest to the torch, denying the Empire vital supplies.

Finally, on the eighteenth of Midyear, the Legions sent to Auridon rejoined the main body and landed on the coast, fully encircling Alinor. The city surrendered, officially ending the war, on the fourth of Sun's Height, 4E 227. The day has since become an Empire-wide holiday.

—The Second Great War by Hadvar of Riverwood, Published 5E 4

Fifth Era Timeline

4E 228/5E 0

Emperor Dovahkaaz I is officially crowned Emperor of a united Tamriel on the first of Sun's Dawn.

The White-Gold Concordat is dissolved.

The Blades are re-formed with Paarthurnax as Grandmaster. The Way of the Voice becomes mandatory training for all agents.

The Nerevarine departs for Akavir, again.

5E 1

The Emperor surprises almost everyone in the Empire by admitting that he has been a werewolf for nearly twenty eight years. This is immediately followed by an edict allowing all lycanthropes of all types to live their lives openly without fear of being hunted by the law merely for being what they are on the condition that they can control their bloodlust. Any that couldn't were hunted down and either relocated to Vardenfell or put out of their misery. This was the first of many racial equality reforms passed by Dovahkaaz.

5E 17

After more than a decade of negotiations, three of the four nations of Akavir agree to join the Empire. The Kamal refuse.

5E 43

The secrets of creating stalhrim are rediscovered. The specially enchanted ice quickly becomes the standard material for the armor and weapons of the Army of the Dragon.

5E 87

Emperor Dovahkaaz I passes away at the age of one hundred forty eight, shortly after convincing the reclusive Maormer to join the Empire. His designated heir becomes Emperor Dovahkaaz II.

5E 117

Led by Knight-Paladin Gelebor, a population of Snow Elves revealed themselves and integrated into the Empire.

5E 481

With the help of the last of his kind, Yagrum Bagarn, the enigma of Dwemer mechanisms was cracked, beginning the Age of Machinery.

5E 509

With new Oculories, many scholars find that Mundus is not limited to Nirn, but may stretch distances that are inconceivable to the common mind.

5E 510

Scholars coin the term "Lorkhan Collective" ("Collective" for short) to refer to a group of worlds revolving around a sun much the same way Masser and Secunda revolve around Nirn, whose Collective holds four other worlds. Nirn is the second world in the collective

The Emperor immediately posts a monetary reward of one hundred thousand Septims to anyone who could devise a way for Scholars to physically study these worlds.

5E 912

A team of Falmer, Argonian, and even two dragon scholars finally develops the solution: the Aetherial Vessels.

Among the new technologies created for these ships are an air creation system, a fully-sealed armored shell crafted from stalhrim, and an engine capable of reaching Aetherius. This engine directs air heated by a hyper-enhanced version of the Flames spell out of the rear of the vessel to propel the ship forward.

In addition, to protect the scholars, the Void Armor, a sealed variant of Ebony, is forged. Two unique enchantments are designed just for this armor: one, a modified version of the Waterbreathing enchantment, provides a lungful of air every time the wearer requires it; the other allows the armor to repair itself.

Construction begins later that year.

5E 927

The first Aetherial Vessel is completed. It is christened the Dragoncat, given a crew of forty scholars escorted by ten warriors from the Fighters' Guild, and launched to explore the Collective.

They learn that one other world would be habitable with the help of Kynareth and appropriately enchanted garments. The rest could be used for mining resources, but little else.

The Emperor quickly sanctioned plans for a colony on this new world, dubbed Talos.

5E 933

The second Aetherial Vessel is built and begins to deliver colonists to Talos. Among them are priests, priestesses, and champions of Kyne, tasked with taming the world for the peoples of Nirn.

At the same time, the Dragoncat delivers the first load of miners to the fourth world.

5E 1781

The entire Nirn Collective has been settled for either mining or habitation.

A network of Aetherial Fortresses has been constructed over Nirn and Talos, hovering over each province's capitol, to facilitate both military and civilian projects.

A new engine type, one that could allow travel between Collectives, begins final development.

5E 1788

The Aetherium Jump Mechanism receives its first large-scale test, retrofitted into the Dragoncat.

The Mechanism allows a vessel to "jump" from Aetherius into a plane of Oblivion; it can them "jump" back at a different point. Sheogorath offers the use of the Shivering Isles, but a deal is eventually reached with Meridia, the Princess of Light.

The Dragoncat's crew proves this concept a success by moving from Nirn to the beyond the revolution of the fifth world, a journey that would normally last a week, in under an hour.

5E 1797/6E 0

The Martin Septim, the first Aetherial Vessel to incorporate an Aetherium Jump Mechanism during construction, makes the first jump to another Collective.

The Lorkhan Collective, the first discovered and explored, has only three worlds, one of which is barely habitable. With most of its land mass covered in disease-infested swamps, argonians were the obvious choice to form the core population of the colony.

Sixth Era Timeline

6E 4

To handle mental activities too complex for scholars to handle, something that was becoming increasingly common, the first Unfettered Minds are created. Originally an illegal research project intending to use soul gems to grant immortality, the Minds are so much more. They are formed by infusing a specially prepared Grand soul gem with the essence of a living being's mind. Freed from the limitations of a physical body, their ability to process information reaches levels only the Divines, themselves, can surpass. When the gem that contains the Mind is docked with an automaton or ship, they can control such objects with speed and precision that a living being cannot match. However, they only choose to take over ships in emergencies when their quicker reactions are required.

6E 58

A new category of automatons meant to closely mimic a living body is created to allow Unfettered Minds to interact with their crew in person. These creations are called Simulacrums. Within a decade, well over a hundred Simulacrums are in service across the Imperial Navy.

6E 781

The Empire now spans thirty seven Collectives with a total population of twenty billion Black Souls and three thousand Simulacrums.

In the Shor Collective, a curious discovery is made. A massive artifact many thousands of feet long is found on the edge of the Collective. Its appearance consists of two connected arms with two connected rings between the arms and near their connection point. While no magical energies are detected, its faint resemblance to the symbol for an Oblivion Gate prompts the Emperor to err on the side of caution and declare that area off limits.

Because of that discovery, a program to arm Aetherial Vessels is begun.

6E 799

The first viable Thunderstorm and Sunfury Cannons (projectors of hyper-enhanced versions of the Lightning Storm and Sunfire spells, respectively) are deployed. The use of these spell types was necessary; in Aetherius, fire dissipated over distance while frost quickly melted. Each cannon is an enlarged soul gem slaved to their particular spell connected to a large battery constructed from pure Aetherium. These Aetherium Batteries contain deep, regenerating reservoirs of magicka.

A dozen ships are quickly retrofitted with these weapons as well as Ward Generators.

6E 801

The first full test of the Cannons occurs. To prepare, the Grey Gate, as the construct is called, is towed out of the Collective. Then the twelve warships lined up and opened fire. The pounding continued for two straight days before the Gate finally broke apart. The flash from its explosion became visible in the skies of Shor two months later.

6E 832

The first Black Souls beyond the Empire are discovered. They are a birdlike beast race that call themselves the raloi. Despite not possessing knowledge of magic, they had advanced quite far, especially in the realm of machines. The raloi are integrated into the Empire, and their Collective, the Turvess Collective, is the first to not be named for a deity.

A Gray Gate is discovered at the edge of the Collective and destroyed.

6E 849

The Wrath of Akatosh, the first Aetherial Vessel to incorporate raloi technology, is launched. At six thousand feet in length, it is the largest ship in the Imperial Fleet. As the first ship to mount an Atomic Fire Engine, an enhanced version of a raloi prototype, it was also the fastest for its time, traveling at three and a half times the speed of the previous Hyperflame Engine, enabling it to cross a Collective in two days. Its armament of three Thunderstorm and eight Sunfury Cannons is the strongest of any warship, as befitting the ship of a commander.

6E 850/7E 0

Having completed its shakedown run, the Wrath is fully commissioned into the Imperial Navy under the command of High Admiral Kesara, second in command of the entire Navy.

For its maiden voyage, the ship is tasked with exploring the newly discovered Vivec Collective, on the edge of the Empire.

When the Wrath arrives, the Collective is found to already be colonized by another race of Black Souls. Contact with the inhabitants introduces the Empire to the larger community in Mundus.