House Baratheon of Storm's End

When Orys Baratheon, a general and close companion of Aegon the Conqueror, married Argella Durrandon, the last of the Storm Kings, he inherited her castle along with its banner and words. That marriage founded the youngest of Westeros's great houses, though through Argella's blood its line reached back to King Durran himself.

Generations on, a grandson of the first lord, Rogar Baratheon, served as Hand of the King and Protector of the Realm during Jaehaerys I's minority; he married the widowed queen Alyssa Velaryon and had two children with her, Boremund and Jocelyn. Later, during the Dance of the Dragons, another lord of the castle, Borros, broke with his father's old allegiance and backed Aegon II: Prince Aemond travelled there to offer a marriage pact in exchange for his swords, and Borros eventually marched on the capital during the Moon of the Three Kings before falling, at the Battle of the Kingsroad, to a young Tully.

Later still, King Baelor I spent more than half a year recovering there from a wound taken in Dorne before gathering strength to return to King's Landing.

In 200 AC the lord of the castle held a tourney to mark his grandson's birth, and nine years later that same grandson, Ser Lyonel Baratheon, already known as Lyonel Stormbreaker, fought alongside Duncan the Tall in a trial of seven at the Ashford tourney.

The match Lyonel had arranged between one of his daughters and Crown Prince Duncan Targaryen collapsed when Duncan married Jenny of Oldstones instead. Furious, Lyonel proclaimed himself Storm King and raised his lands in revolt, a rebellion Duncan the Tall ended in single combat. As amends, King Aegon V offered his youngest daughter, Rhaelle, to Lyonel's heir, Ormund; they wed at Storm's End in 245 AC, and Steffon Baratheon was born the following year.

Steffon Baratheon grew up at court in King's Landing, where he became close friends with his cousin, Prince Aerys. In 260 AC he fought in the War of the Ninepenny Kings and watched his father, Lord Ormund, die there at the hands of Maelys Blackfyre. His eldest son, Robert, he entrusted to Lord Jon Arryn, who raised him at the Eyrie alongside Eddard Stark of Winterfell.

After the Defiance of Duskendale, King Aerys II called him to his small council, and in 278 AC sent him to Volantis, with his wife Cassana Estermont, to find a bride for Prince Rhaegar. The search failed, and on the way home the ship carrying the lord and lady of Storm's End sank, killing them both.

Robert inherited the castle on his father's death and was betrothed to Lyanna Stark of Winterfell. At a tourney held at Storm's End itself, Ser Barristan Selmy won the joust against him.

When Prince Rhaegar vanished with Lyanna in 282 AC, her brother Brandon Stark rode furious to King's Landing; Aerys II had him executed alongside their father, Lord Rickard, and demanded the heads of Robert and Eddard Stark as well. Jon Arryn refused and called his banners, and the war began. Robert would go on to kill Rhaegar himself at the Battle of the Trident in 283 AC, while in the Stormlands his house's forces fought at Summerhall and withstood the siege of Storm's End.

With Robert crowned king and settled in the Red Keep, the family split three ways: he kept King's Landing, Stannis received Dragonstone — left empty by the fleeing Targaryens — and the youngest brother, Renly, took over Storm's End.

In time Renly also won a seat on his brother's small council as Master of Laws, by then established as lord of the family castle.

When Lord Jon Arryn died suddenly, Robert travelled north to offer the Handship to his old friend Eddard Stark. Renly rode out to meet him, and back in the capital took part in the Tourney of the Hand, where he fought well before losing to Sandor Clegane.

With Robert dying after a boar's attack, Renly asked Eddard to back his claim to the throne over Stannis's. Eddard refused, certain the crown belonged to the surviving elder brother, and that same night Renly left the capital with Ser Loras Tyrell and his men. The new king later named him among those who had to swear fealty in person or be branded traitors.

Renly brought the whole of the Stormlands to his cause along with much of the Reach, backed by House Tyrell; Stannis, by contrast, had little beyond the royal fleet and the men of the crownlands.

The two armies gathered before Storm's End ready to settle the war by force, but Renly died there without an heir. Most of the houses sworn to him, along with more than a few from the Reach, went over to Stannis, who then attacked King's Landing at the Battle of the Blackwater and was defeated; afterward nearly all who had followed him bent the knee to the Iron Throne.

The garrison Stannis had left at Storm's End, under Ser Gilbert Farring, stayed loyal even after his defeat. With Renly dead, his widow Margaery Tyrell remarried, this time to the boy king Tommen, and the regent queen Cersei Lannister sent Lord Mace Tyrell to take the castle.

Mace barely began the siege: on learning his daughter Margaery had been arrested, he marched his army back to the capital and left Lord Mathis Rowan in charge of a much smaller force to keep it up. Over time that garrison became Stannis's last holdout in the south, pressed by Rowan and also by the arrival of a Targaryen claimant leading the Golden Company.