Ubbe, the eldest son of Ragnar and Aslaug, is one of the fans' favorite Sons of Ragnar in Vikings. He may not quite manage to edge out Bjorn for the title, but compared to the villainous Ivar and his other brothers, Ubbe is clearly one of the most heroic of the brothers.
Despite the fact that Ubbe is definitely one of the better Sons of Ragnar, he certainly has his flaws, and his fair share of bad decisions behind him. From his attacks on England to avenge his father's death to his eventual journeys to Iceland and beyond, Ubbe tends to pave his own way, and this often puts him in serious conflict with others. He manages to find a happier end than most other characters, though, so he must have made a few good decisions along the way.
Worst: Venturing Out Onto Thin Ice
This may seem like a small decision, especially compared to the many times that Ubbe was making major battlefield choices that would affect so many more lives. However, when he ventures out onto a frozen lake as a child (along with Hvitserk), and they crash through the ice, Siggy loses her life to save them.
Best: Staying In Kattegat
For much of the series, when Ragnar or the others Sons of Ragnar are heading out into the world, Ubbe is often found staying behind in Kattegat to protect the town and rule the people. And more often than not, this is a smart decision. Especially when Ragnar is attempting to find people to go with him back to England for the last time, Ubbe's decision to remain where he was may have saved his life. Ivar was spared in part because he was not seen as a threat - but Ubbe definitely would have been. He would not have saved Ragnar's life, and he may have lost his own, too.
Worst: Marrying Margrethe
Ubbe's first wife was Margrethe, an enslaved woman who was freed to allow her to marry him. At first, this seemed like a good match, and one made for love, however, it quickly became clear that Margrethe was becoming unhinged. She started to push Ubbe to try and betray Lagertha, to kill Bjorn, and to take over Kattegat, and eventually she became completely insensible. She was eventually killed by Ivar, after Ubbe had to leave her when he fled to England.
Best: Marrying Torvi
In stark contrast to Margrethe is Torvi, the woman that Ubbe married after her, and who was a perfect partner to him. Unlike his first wife, Torvi has no desire to rule or take over, and is a deeply loyal and compassionate person.
Her relationship with Ubbe helped cement Ubbe's connection to Lagertha, and she continued to support him through the rest of his life.
Worst: First Going To Paris
Admittedly, Ubbe may not have had much of a part in this decision, but when he was brought to an attack on Paris by Ragnar, it was clearly a problem. He and his brother were brought along despite being too young to fight, and ended up in serious danger. More than that, they saw Ragner kill Yidu by drowning her, something that was the start of the break between Ragnar and Ubbe.
Best: Trying To Make Peace With The Saxons
During all his battles in England, Ubbe was most driven to try and make peace with the Saxons, and to live out his father's dreams of being able to settle there, and to build new lives in this land. While this was something that never came to real fruition (thanks largely to Ivar, but also to Ecbert's own treachery), his motivation and his attempts to create peace were the right choice. This also helped him survive when he had to flee Kattegat after Ivar's attack, when he was able to find a way to live in a kind of harmony with Alfred, who saw in Ubbe the same drive for peace that he himself had.
Worst: Setting Himself Against Ivar
The break between the Sons of Ragnar set in motion a series of wars and battles that would kill far too many - and that could have been prevented if Ubbe had found a way to reconcile with Ivar. It was clear that Hvitserk was unsure of himself, and would never have stood against Ivar and Ubbe if they were in agreement. And with Bjorn wanting to leave to explore, and Sigurd dead, it really came down to these two.
While it's easy to see why Ubbe couldn't remain with Ivar, because of Ivar's bloodthirsty behavior, his decision to stand as an enemy was the start of a lot of misery.
Best: Aligning Himself With Lagertha
While many of Aslaug's sons were ready to hate Lagertha, and never truly forgave her for killing their mother, Ubbe was the one who was able to move past it and become a true ally to her. Together, these two made an extremely powerful pair, and Ubbe's decision to not hold a grudge was one that made a huge difference in the end.
Worst: Leaving Kattegat For Iceland
In the final seasons of Vikings, Iceland comes into play - first discovered by Floki, and then settled by a group from Kattegat, before Ubbe and Torvi finally head to this new land. They make this decision in part to find Floki, but also to try and seek the way to a different land - yet, for a time, it seems as though Iceland would be the end of them. Flatnose was increasingly power-hungry, and after a whale appears on his land and he refuses to share it, a minor battle breaks out - and Torvi and Ubbe only barely escape.
Best: Leaving Iceland Behind
This may not be so much a 'decision' in the traditional sense, as Ubbe and his followers were fleeing the fight with Flatnose, but it was still one of the best moves that Ubbe made. This voyage would take them to North America, where they found a land richer than their wildest dreams. Here, they also found Floki, and made a peace with the local Indigenous people - giving Ubbe possibly the best ending of any of the Vikings characters.