The Tournament of Longtable was held in 456 AC and hosted by Lord Owen Merryweather in honour of the birth of King Orys II Baratheon's son, Renly Baratheon. It was initially planned to be a twelve day affair, but was cut short by the death of the king's brother, Ser Colen Baratheon.

The Joust
Lady Merryweather began the tourney as the Queen of Love and Beauty, and three champions swore to defend her title: Her eldest son, her uncle, and Ser Lucas of the Red Fronds.
There were three days of jousting.
Known Tilts
Ser Colen Baratheon defeated Lady Merryweather's son
The Grey Knight defeated Lady Merryweather's uncle, won all six tilts
An unnamed member of the Kingsguard defeated Ser Lucas of the Red Fronds
Hors Umber defeated the unnamed member of the Kingsguard
Ser Colen Baratheon defeated three unnamed opponents
The Grey Knight defeated five unnamed opponents
Champions
Ser Colen Baratheon, Hors Umber, and The Grey Knight.
An agreement could not be reached on choosing the new Queen of Love and Beauty, so King Orys II Baratheon declared a melee for the following day, the winner of which would choose the new Queen.
The Melee
Hors Umber yielded
The Grey Knight killed Ser Colen Baratheon when a tourney blade slipped under the man's gorget.
In his fury, King Orys forced the Grey Knight to remove their helm, intent on killing the man beneath. Instead he discovered Victaria Greyjoy, and could not bring himself to kill a woman. This is believed to be the beginning of Orys II Baratheon's hatred for the Ironborn.
Other Attendees
Lord Theomar Swann, Ser Mark Osgrey, Lord Richard Gower, Lady Merianne Baratheon, Lady Selyse Selmy, Lord Davos Seaworth
Important Events
Ser Colen Baratheon, the King's brother, was killed during this tourney. His killer, The Grey Knight, was subsequently unmasked and discovered to be Victaria Greyjoy. This is believed to be the beginning of Orys II Baratheon's hatred for the Ironborn which cumulated into the disdain that caused the Second Greyjoy Rebellion.