Coronation of Aegon I

The High Septon places the crown on Aegon the Conqueror's head at Oldtown, and with that gesture the claimant becomes Aegon I Targaryen, king of the six realms he has brought to heel. From that moment maesters start counting years from zero: everything before is marked as the past, everything after is numbered after the Conquest.

The same year is sealed with a marriage that founds a new house: Orys Baratheon takes Argella Durrandon as his wife, and from that union House Baratheon is born.

Now crowned, Aegon divides the rule of the lands he has unified among the houses that bent the knee to him or served as his allies. To the Baratheons he grants the paramountcy of the Stormlands; to the Tullys, that of the Riverlands; to the Greyjoys, that of the Iron Islands; to the Tyrells, rule over the Reach along with the wardenship of the South.

The North is left to the Starks as wardens, the west to the Lannisters, the east to the Arryns. To House Qoherys he grants lordship over Harrenhal. With this division, the king leaves behind seven separate kingdoms and raises in their place a hierarchy of great houses answering to the Iron Throne.