The War of the Brothers was an Essosi conflict started by a pair of Volantine sellswords. They were one of many who attempted to unite the Free Cities
The sellswords Thoros Lozegros and Lysono Lozegros were widely considered to be the best killers in Essos, and they formed their own company in 350AC. They fought in many conflicts across the continent of Essos and through their deeds their renown and numbers swelled.
When a Dothraki Khal came out of the east, threatening Volantis in 361AC, the brothers, who now named themselves the Brothers Magnificient were given command of the Volantine hirelings. They fought a vicious campaign across the city's borders, with the Khal coming within a day's ride from Volantis's walls before being beaten back. They were able to drive the khalasar off, after killing its leader in single combat.
They had earned the trust and respect of their comrades over the course of the conflict, which lasted two years and caused thousands of deaths. After the defeat of the Khal, the remaining sellswords swore themselves to the brothers as their new leaders. This new host would drive back the remaining horselords all the way to the ruins of Essaria, becoming known as the Thousand Banners upon their triumphant return.
The Begining of the Conflict
The war with the Khal had been costly for Volantis, both in men and money, and the Triarchs did not have the gold to pay the Thousand Banners the huge sums that had been pledged. The Brothers themselves were instead given the chance to take any treasures from inside the Black Walls.
There, they found two of the crowns that the Triarchs had worn during the Century of Blood, when they had attempted to rebuild the Freehold. The Thousand Banners set off for the city of Volon Therys, where, drunk on victory and in rage about the non-payment, they sacked the city in an orgy of blood and fury that would have the Sealord of Braavos name Lysono and Thoros "the Brothers Malevolent."
The Sack of Volon Therys
The city had been already set up as a camp site and musterground for much of the war, and the arrival in was heralded with much feasting and revelry. As the night wore on though, the sellswords began to take more liberties. According to popular legend, the killing is said to have started when a young noblewoman slapped Lysono's hand from her breast. Her father is said to have stepped between her and the now fuming sellsword, and was struck down immediately. The sack began soon after, although others point to a duel gone wrong as the reason.
Following the sack, Lysono and Throros crowned themselves Co-Kings of Essos, riding attop thrones borne by their new conquests. Their first edict was the mass enslavement of many of the survivors, in the name of recruitment. Their host swelled to twice it's size, with a huge convoy of retainers, they set off west, to stake their claim.
The Battle of the Blossoms
Following news of the horrors of Volon Therys, the shocked Triarchs called a conference of any cities that would come to their aid. They set their own host north, hoping to catch the new Kings before they reached Valysar.
The Kings were able to confuse the Volantine outriders, finally meeting them in a huge orange orchid. The battle is said to have lasted less than an hour, as the thick blossoms made it difficult for the Volantine host to see the disperal of the enemy. Less than one in three of the army ever made it back to Volantis.
The Capture of Valysar
A council of city leaders led Valysar's watch in a futile defiance. One of the men amused Thoros enough whilst fighting that he took the dead man's family when the city was yielded.
The Kings wouldn't wait in the city long though, Myr and Braavos were massing a host in the Disputed Lands, and set off not a week after the city yielded.
The Battle of Bonehill
The Thousand Banners met the combined Myrish and Braavosi host on the foothills west of Valysar. The Myrman commanding was said to be so certain of his men that he allowed them an extra night before engaging the enemy.
The Kings were able to win over many of the sellswords during the night, and attacked the camp in the early morning. The remnants of the Braavosi-Myrish army was only saved by the timely intervention of a Lysene fleet. It would later emerge that the Brothers had masked their true position by setting several fires further up the hills and camping in a dip.
The Battle for the Disputed Lands
Following their victory, the new Kings drove themselves even further west, claiming the Disputed Lands as their own Crownlands. Setting a huge wood and stone keep on the shores of the Northern Lake, they set to capturing or raiding across the entire area.
However, Lys and Tyrosh had both joined Myr and Braavos's coalition, strengthening their resistance. Over the next year, three armies would be sent out from the Free Cities. The Braavosi General Tyrio and the Lysene Captain Harro Lohar would lead them, keeping their movements quick and out of the grasp of the Co-Kings, and striking wherever was weak.
However, none would meet with true victory, and after a summer rain held up the progress of the coalition retreating north, Lysono and Thoros smashed it, sending it routed towards Myr.
The Battle of Myr
Frustrated from the raiding and guerilla warfare, the Brothers Magnificient were raring for a battle. As Tyrio and Harro's army fled, the Thousand Banners followed. Pentoshi reinforcements met the coalition host at the city, and it's commander, Prince Rhaevo suggested a daring feint to draw the Co-Kings north.
Sacrificing much of their number, the army of the Free Cities appeared to break, pulling north onto the Pentoshi Flatlands, fortifying a harbour town.
The Brothers were torn on how to proceed, with many in the army tired and wanting to sack Myr. However, they decided instead to follow the host, thinking to trap and crush the army.
The Battle of the Flatlands
Unbeknownst to the Brothers however, Bravos had sent a small host to the town already. Led by the First Sword (a name strangely absent from history, with legends claiming he was everyone from the grandson of Danaerys Targaryen, to the third brother of Lysono and Thoros,) the small host joined it's strength and waited.
The Thousand Banners was fatigued by the time that they reached the small town, but the Kings sent them forward. The flanks of their attack were initially repulsed, but the coalition forces fell back before the centre, which the kings led themselves.
As they entered the town, Thoros espied the First Sword, who sat calmly oiling his blade in the town square. Thoros is said to have laughed and asked the man if he knew that the battle had begun. The First Sword is said to have simply challenged the man, and to have replied "I know that it is almost over."
Thoros fought a fierce duel with the man, fighting with his huge arakh, but eventually, he succumbed to the many light wounds. Lysono, it's said, saw his brother's wounded body dragged from the square, threw down his crown and leapt at the man himself. The Braavosi only cut the King once, merely avoiding all of the sellsword's blows. Then he revealed the poison on his blade.
Lysono died in the square, and the Thousand Banners routed soon after. Thoros, body destroyed from the toxin, was still able to escape to the isle of Sunstone, with some of his retainers and the many bastards of him and his brother where he passed the motley cloak sown from the banners of the company to his brother's eldest, Caerys of Burnthill.
The Company continued on, now formed of solely those descended in the male line from the brothers, now taking the insult of the Brothers Malevolent as their name. The fragile peace between the Free Cities fostered by their cooperation would not last long, with Braavos openly blaming Volantis for the whole affair.
The memories of the Co-Kings would last though, and since, effigies are burnt of them in Volon Therys on the anniversary of the sack.