Viserys was the grandson of King Jaehaerys I Targaryen and Queen Alysanne. Jaehaerys lived to such an old age that he outlived his own son and heir, and upon his death in 103 AC it was Viserys who inherited the crown. In his youth he rode Balerion, until the Black Dread passed away, and he refused to ride any other dragon in his lifetime.
Reign and marriages
Viserys ruled during a time of peace and plenty. His grandparents had spent most of their lives and reigns ordering the realm, encouraging peace and diplomacy between the kingdoms. His rule was remarkably free from incident, and may be the most peaceful of any king of the unified Seven Kingdoms to date.
Viserys' first marriage was with his cousin Aemma Arryn(a half-Targaryen on her mother's side), who could only give him a daughter, Rhaenyra, while his two sons died in infancy and Aemma died giving birth to their latest child.
Some years later, Viserys remarried to the daughter of his Hand, Lady Allicent of House Hightower who gave him three sons and a daughter in rapid succession. It was expected that Rhaenyra would succeed him as the first ruling queen of Westeros. To this end, he kept her close during council meetings and audiences, schooling her in the art of rulership. Rhaenyra, ten years older than her eldest half-brother Aegon, did not anticipate them disputing her succession, and neither did Viserys, for he continued to treat Rhaenyra as his heir.
He died in 129 AL and it was anticipated that Rhaenyra would inherit. Instead, Ser Criston Cole of the Kingsguard instead took King Viserys' crown and gave it to his son Aegon, who claimed the Iron Throne as Aegon II. Rhaenyra disputed this, triggering the civil war known as the Dance of Dragons.
Character and appearance
Viserys Targaryen was a pleasant, open-handed and generous man, raised in a time of great prosperity. He was plump, friendly and fair, known for his sense of humour. Viserys was known to wear the crown of his grandfather Jaehaerys I Targaryen. He was beloved by his people and the vast majority of his subjects. Viserys doted on his children, particularly his eldest daughter, and proclaimed her his heir until the end of his days, although this proclamation would mean fire and blood for Westeros after his death.
His relationship with his brother Daemon wasn't an easy one, especially when he joked his son Baelon, who died a day after his birth, had been 'Heir for a day'. Viserys tolerated his brother's campaigns in the east so long as they 'kept him out of trouble', but was reasonable enough to accept him back at court after Daemon discarded his crown and returned to Westeros. It is remarked by many that Viserys held Daemon in sentiment, having remembered the lad that Daemon was in spite of the man he became. He was generous enough to give Daemon prodigious positions on the small council.
Viserys was a fundamentally good man to start with, but as he got older, he became more aggressive, surly and even violent. Weary of the feuding between his wife Alicent, and his daughter Rhaenyra, Viserys made many fruitless attempts at reconciling them. When rumours persisted that Rhaenyra's children were bastards, Viserys threatened to cut out the tongues of any man who said so. His efforts to reconcile his feuding wife and daughter actually fanned the flames of their animosity, though it would be untrue to say that this was Viserys' intention, or indeed in his control.
While a good and well-liked king, Viserys was not a good judge of character, and prone to grievous mistakes when it came to other people. While his love for Rhaenyra was all well and good, his expectation for the other lords of Westeros to simply comply with his wish that she inherit the throne after him was misplaced and woefully dangerous in and of itself. He was also far too tolerant of the feud between Alicent and Rhaenyra, upon marrying her; because he legitimately loved both women, he showed restraint when it came to them. This grew to the extent that he thought Alicent would respect his wishes with regards to Rhaenyra after his death, and was indescribably wrong in this regard. That said, even Rhaenyra was willing to say that Viserys loved Alicent.
Viserys was not a warrior, and tended to wear silks in dark colours reflecting his house sigil. He had a bushy silver-gold moustache, but no beard. He wore his grandfather Jaehaerys' simple crown. Rhaenyra would go on to wear it after his death. Viserys was very fat towards the end of his life, struggling to climb to the Iron Throne eventually.