House of the Dragon has become a huge hit since its debut. As an adaptation of part of George R. R. Martin's book Fire And Blood, the prequel series focuses on Targaryen history. House of the Dragon introduces many exciting characters into a familiar world, including Viserys I Targaryen.

RELATED: House Of The Dragon: A Complete Timeline Of Targaryen History

King Viserys' various decisions influence and pave the road towards the Dance of the Dragons civil war. Played brilliantly by Paddy Considine, Viserys is a likable ruler, but he has made numerous mistakes that have defined his reign as a weak king. These errors include lapses in judgment or allowing others to further their own name at his expense.

Spoilers ahead for House of the Dragon.

10 Viserys Prematurely Threw A Tournament To Celebrate The Birth Of An Unborn Son

House of the Dragon has Otto Hightower as its Littlefinger

The first of King Viserys' many mistakes in House of the Dragon came when he arranged the Heir's Festival. To everyone else, it seemed incredibly confident to assume that his wife would finally give birth to a baby boy, but they didn't know about Viserys' dragon dreams. In these dreams, Viserys had seen his son sitting on the Iron Throne, but he wrongly presumed this referred to Aemma's current pregnancy.

By arranging a grand jousting tournament prematurely, Viserys looked like a fool when disaster struck later on. The tournament was still an entertaining spectacle, but instead of welcoming a new heir, it welcomed a host of entirely new problems.

9 Viserys Killed Aemma In The Name Of Having A Son

Lady Aemma Arryn Targaryen speaks with Princess Rhaenyra in House of the Dragon.

When Viserys was called to Aemma's bedside during the tournament, he was presented with a choice. Mellos explained that the king could either allow them to kill Aemma to save the baby or do nothing and leave both of their fates to the gods.

Viserys' obsession with having a son to further the Targaryen legacy drove him to kill his wife, an act that would haunt him for years to come. When the baby didn't survive the aftermath, all that trauma was for naught. Viserys would keep his tragic decision a secret until he told Alicent about it in a drunken state.

8 Viserys Gave Daemon Power By Naming Him Commander Of The City Watch

Matt Smith as Daemon in House of the Dragon

No matter how long he has left, Viserys will love his family for the rest of his life. However, his family members have a habit of getting themselves into trouble, which has always tested his patience. Viserys tried his brother Daemon in various roles on the small council, from master of laws to master of coin, but Daemon hated governance and other mundane roles.

RELATED: House Of The Dragon: 10 Things Only Book Fans Know About Daemon Targaryen

Although Daemon only wanted to be named his brother's Hand, he was eventually made the Commander of the City Watch. He thrived in this role. However, the role unlocked Daemon's vicious side. He led a purge of criminals and showed no mercy. While this brought crime down considerably, it caused tensions in the small council and extra grief that Viserys didn't want or need.

7 Viserys Pushed Daemon Away And Angered Him

King Viserys I Targaryen and Daemon Targaryen talking in House of the Dragon.

Daemon had wanted to be Viserys' Hand of the King for a long time, but as well as being pushed around several roles, he was also married off to Rhea Royce of the Vale. Daemon felt abandoned by his family, which led him to act out in pure pettiness and misguided spite.

Viserys didn't know that Daemon would act like this, as he was unaware that his brother wished to be Hand of the King. He angered Daemon further by pushing his brother down the line of succession, first with Rhaenyra and then with Aegon. Daemon was unpredictable at the best of times, but these slights made him dangerous to anything the king would plan or hold dear.

6 Viserys Chose Alicent Hightower Over Laena Velaryon

Alicent Hightower and King Viserys I Targaryen with the infant Aegon Targaryen in House of the Dragon

Under advisement from his Hand at the time, Otto Hightower, Viserys often rejected suggestions and requests from Corlys Velaryon. The Velaryons rarely received the respect they deserved from the crown anyway, but Otto's meddling would make the relationship even worse.

RELATED: 10 Best Quotes In House Of The Dragon (So Far)

With the king mourning the loss of his wife and son, Otto had his daughter Alicent visit the grieving king and offer him comfort. Viserys was advised to marry Corlys Velaryon's daughter Laena, but when the decision time came, he shocked everybody by naming Alicent as his future wife. With Alicent giving Viserys multiple children, the Hightowers have a grip on the royal line. They will likely be a nuisance going forward in House of the Dragon.

5 Viserys Created Tension With The Ancient House Velaryon

Corlys Velaryon and Rhaenys Targaryen talking to King Viserys Targaryen in House of the Dragon

Viserys' decision to marry Alicent furthered the rift between the Targaryens and Velaryons. It started with Viserys being chosen as monarch over Corlys' wife Rhaenys and was worsened by not helping with the conflicts in the Stepstones. Viserys would later have to work hard to repair the relationship. Following council from Lyonel Strong, he sought to bridge this gap by marrying Rhaenyra off to Corlys' son, Laenor.

Due to the disrespect shown to House Velaryon, honor dictated that Viserys had to travel to Driftmark to make the marriage official. It was a treacherous and rocky trip on the seas that he wouldn't have made had he not furthered tensions with Corlys in the first place.

4 Viserys Feared Breaking The Peace So Refused To Help In The Stepstones

An image of Daemon wearing a crown in House of the Dragon

The issues in the Stepstones were far more serious than Corlys Velaryon simply wanting aid in defending the seas and coastlines. The war against the Triarchy threatened the peace that Viserys prided himself on keeping, but he would still refuse to entertain the notion.

This lack of action caused people to perceive Viserys as a weak king. He eventually offered to send help to the efforts, but this only angered his brother Daemon. Daemon was prompted to end the war quickly before Viserys could take any credit for himself. An early showing of strength from the crown could have gone a long way in changing the perception of Viserys.

3 Naming Rhaenyra Heir Created Unrest And Uncertainty

Viserys and Rhaenyra looking at fire in House of the Dragon.

Viserys' obsession with having a son drove him to kill Aemma. In his grief, he could never see the big picture of remarrying and having more children, so he finally sought to reconcile with his daughter, Rhaenyra. Despite being advised not to do so, Viserys named her his heir. This defied the age-old tradition of men ruling Westeros.

RELATED: 10 Most Interesting Locations In The House Of The Dragon Universe, Ranked

While fans can get behind a family-fueled decision like this, the cruel world of House of the Dragon cannot. Naming Rhaenyra as his successor ultimately planted the seeds for the Dance of the Dragons, the Targaryen civil war.

2 Viserys Allowed Rhaenyra To Choose Her Husband

viserys and rhaenyra targaryen face to face in House of the Dragon

Having named his daughter as his successor, Viserys then struggled to keep her under control. He tried to force tradition onto Rhaenyra with a forced marriage, but her feisty personality objected. She threatened to make everything even harder. Despite having a son with his second wife Alicent, Viserys chose to double down on supporting his daughter in succeeding him.

As a token of his promise, Viserys granted Rhaenyra leave to choose her own husband. He paid for his daughter to go on an extravagant tour where she received a host of proposals at different locations. However, Rhaenyra quickly grew bored with the process. Viserys eventually convinced her to enter a forced marriage with Laenor Velaryon anyway, meaning money and time were wasted on the tour.

1 Viserys Allowed Rhaenyra To Influence Big Decisions Before She Was Ready

Rhaenyra in episode 4 of House of the Dragon

With Rhaenyra named as Viserys' heir, she quickly began to test the waters by interrupting a small council meeting. Viserys berated her but allowed her to choose the new member of the Kingsguard. She used logic to choose the one candidate with combat experience, which was Criston Cole, but his inexperience and lack of an established name would have serious consequences later down the line.

Rhaenyra also managed to sway Viserys into firing Otto Hightower as his Hand, a vitally important decision that Viserys lacked the conviction to do otherwise. He only went through with it when Rhaenyra agreed to marry Laenor Velaryon in return. This was another showcase of Viserys' weaknesses as a king.

NEXT: Every Known Game Of Thrones Successor Show In Development