Great Tourney at Harrenhal

"...a great southern lord held the largest tourney Westeros had ever seen in the largest castle Westeros had ever seen. Knights and lords from across the Seven Kingdoms made their way, drawn by spectacle and the size of the champion's purse. Even the king was rumored to be attending, though none had seen him in years."

- Meera Reed

The Great Tourney at Harrenhal was the largest tournament held in the history of Westeros. Hosted by Lord Walter Whent in the Year of the False Spring, the tourney proved fateful for the future of the Seven Kingdoms, as Crown Prince Rhaegar Targaryen crowned Lyanna Stark the Queen of Love and Beauty at the end, forsaking his wife Elia Martell and leading to Robert's Rebellion.

History
During the Year of the False Spring, in the height of summer, Walter Whent hosted the largest tourney in the history of Westeros, attracting knights and lords from across the Seven Kingdoms with its spectacle and large champion's purse. Some believe that the entire tourney had in fact been organized by Crown Prince Rhaegar Targaryen to gather the great lords of Westeros and address the madness of his father, King Aerys II Targaryen, perhaps even to remove him from the Iron Throne.

At the onset of the tourney, the young Lord Howland Reed was assaulted by squires to knights from Houses Frey, Haigh and Blount, but was saved by Lyanna Stark, the fierce and willful daughter of Rickard Stark, the Warden of the North. During the evening, a feast was held to mark the opening of the tourney. Lord Howland attended at the behest of Lyanna and her brothers Brandon, Eddard and Benjen. There, a brother of the Night's Watch attempted to recruit knights for the order, only to be met with snickers and smiles. Crown Prince Rhaegar Targaryen played his harp and sang a song so sad that it brought tears to Lyanna. When Benjen teased her, she poured a cup of wine over his head, while Lord Robert Baratheon defeated Ser Richard Lonmouth in a wine drinking game. Meanwhile, the beautiful Ashara Dayne danced with Ser Barristan Selmy and several others, including the shy Eddard, after Brandon had asked for the last dance on his behalf.

However, the hall soon went quiet as King Aerys entered with his Kingsguard. Having not left the Red Keep in years, he shocked everyone with his long yellow fingernails, tangled beard and unwashed matted hair. He would go from hysterical laughter to weeping to rage within moments, making his madness plain for all to see. However, a cheer burst from the crowd as he called forth Ser Jaime Lannister to kneel before him and swear the oath of the Kingsguard before half the lords of the Seven Kingdoms, as Ser Jaime was admired for his courage, gallantry and swordsmanship.

During the proceedings, Howland spotted the three squires who had attacked him standing with their knights, and Lyanna and her brother offered to help him prepare for a jousting match against the knights. Howland refused, and instead knelt on the shore of the Gods Eye and looked to the Isle of Faces, praying to the Old Gods of the Forest. The next morning, the three knights defeated their opponents and earned a place among the champions, only to be met by a mystery knight in the afternoon. Known as the Knight of the Laughing Tree, he wore ill-fitting armor cobbled together from different suits and held a shield painted with a laughing heart tree, the carved white weirwood of the Old Gods.

The three knights all fell before him, and the common folk cheered him, as the knights were not well-liked. At the Knight of the Laughing Tree's behest, the knights chastised their squires for attacking Howland, and were thus allowed to keep their horses and armor. King Aerys was infuriated, and suspected a traitor, possibly Ser Jaime, whom he had already sent to the Red Keep. Declaring the Knight of the Laughing Tree his enemy, Aerys ordered Lord Robert to unmask him. The following morning, however, he was nowhere to be found, and his shield hanging from a tree was all that was ever found.

During the tourney, Lord Commander Gerold Hightower broke three lances against Ser Oswell Whent and fought with great distinction in the mêlée, while Ser Arthur Dayne defeated everyone in the jousts except Rhaegar. Upon unhorsing Ser Barristan, Rhaegar won the joust, rode past his wife Elia, and crowned Lyanna Stark his Queen of Love and Beauty, leaving the crowd silent and shocked.

Aftermath
Shortly after the tourney, Rhaegar supposedly abducted Lyanna, leading to her brother Brandon riding to King's Landing and demanding justice from Aerys. However, Aerys responded by imprisoning him and sending for his father, Lord Rickard. While Rickard beckoned for the release of his son, Aerys had both of them cruelly executed and ordered Lord Jon Arryn to hand over Eddard Stark and Robert Baratheon. Instead, Lords Arryn, Stark and Baratheon rose up in rebellion, leading to the deaths of Aerys and Rhaegar and the overthrowing of House Targaryen in what became known as Robert's Rebellion.

Unbeknownst to most, however, Lyanna had not been abducted. Rather, she had eloped with Rhaegar, and married him in a secret ceremony in Dorne. Together, they had a son who would become known as Jon Snow.