History's Vikings has captivated viewers with its emotional drama, authentic themes, and thrilling battles. Now midway through its 6th and final season, the show's gathered momentum as both the action and the stakes reach a fever pitch. One of the strongest traits of this historical journey is its slew of bold and memorable characters, who often find themselves at odds with one another. As you'd imagine with a show revolving around this warrior culture - battles are waged, factions have formed, and heated rivalries reach a boiling point.

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Hirst's action-drama presents several compelling rivalries, though at least a handful of them leave us scratching our heads. So let's grab our swords as we examine 5 of the best, most memorable rivalries, along with 5 that just make no sense.

Makes No Sense: The Feuding Families Of Iceland

Vikings group in Iceland

One can't help but feel for Floki as he tries to essentially build a new settlement from scratch late in the series. This would be a tough enough task by itself - but he must also navigate a building feud between the families of Kjetill "Flatnose" and Eyvind, and their respective sons Thorgrim and Bul. After deathblows are exchanged by the children of both families, Eyvind is banished, but not before the damage is done.

It's well known that Viking culture largely revolved around conflict and brutality. Still, given the harsh, desolate conditions of this Icelandic setting, one would think petty squabbles could be put aside for the greater good. If ever there were a time for comradery and cooperation, this would have been it.

Best: Alfred Vs Aethelred

It's only natural for siblings to squabble on occasion, though this one goes a step beyond. Following the death of Kings Ecbert and Aethelwulf, 2 potential heirs of Wessex find themselves at odds with one another. Aethelred is the legitimate son of Queen Judith and oldest heir, but the popular Alfred is made king - leading Aethelred to plot against him. Considering Alfred's given the blessings of King Ecbert as essentially "the chosen one," this is a fatal decision for the ambitious prince.

Unfortunately for the prideful Aethelred, his plot was unearthed and dealt with, tragically by his own mother. This rivalry is significant, and at times, quite emotional. It illustrates the harsh politics and conflict of rulers of the Medieval era - often transpiring within the same family!

Makes No Sense: Ivar Vs Hvitserk

Hvitserk accompanies Ivar during the battle of York in Vikings

The dynamic between these 2 distinct sons of Ragnar Lothbrok is a bizarre one, to say the least. Though there are frequent "butting of heads" between his ambitious sons, these 2 can never seem to figure out if they're allies or not. At one moment, Hvitserk s up with Ivar to wage war and take Kattegat, the next he's fleeing to up with Ubbe and Bjorn, before changing his mind again.

His motivations in ing with Ivar are puzzling - given the number of times he's been slighted and wronged by his brutish sibling. It can perhaps be chalked up to the "follower" meshing with Ivar's leadership qualities. Yet, this would seem to have the workings of a greater rivalry if only Hvitserk stood by his convictions rather than bend to Ivar's will.

Best: King Horik Vs Yarl Borg

Yarl Borg leading a fleet to battle in Vikings

Vikings eventually crescendos into a slew of political conflicts, social maneuverings, and warfare. Yet, there's something to be said about this more straightforward land dispute between 2 Viking rulers early in the series. It's an effective way to set the scene for the audience, giving them a taste of cutthroat nature of this culture, and of what's to come. This conflict is significant for Ragnar as he's forced to choose a side, further escalating his role in society.

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It's also a bit of foreshadowing into the eventual larger betrayal of Rollo as he s with Borg to take on his brother Ragnar.

Makes No Sense: Lagertha Vs Kalf

Kalf's decisions and motivations in turning against Lagertha are odd, to say the least - leading to a memorable act of vengeance by the scorned ex-wife of Ragnar. He's first called upon as a trusted caretaker of Hedeby by Lagertha, on the cusp of dealing with a rebellion before ing up with the rebels. He then undergoes the dangerous plot to usurp her Earl of Hedeby, only to back down and agree to marry the Earl and rule side-by-side with her.

Given Ragnar's influence, and the often vengeful, fighting nature of Viking culture, Kalf was certainly playing with fire, especially after attempting to have Bjorn assassinated. This was a rivalry that was pitifully one-sided, and an ill-advised one for Kalf.

Best: Ecbert Vs Ragnar

Ragnar and King Ecbert argue about the importance of the gods in Vikings

The dynamic between these 2 major figures is a deep and endearing one that tends to waver as the show goes on. These are two ambitious fighters who - as mentioned in the show - are similar to each other, despite being mired in quite different cultures and ruling different lands. You've got a Pagan king and a Christian king who seek power and influence but through very different methods.

While there's an ongoing tug of war for power between these Wessex and Scandinavian kings, they still hold a level of respect for one another. Their final scene together shortly before both men perish is a touching one, rife with some memorable dialogue.

Makes No Sense: Lagertha Vs Aslaug

Vikings Aslaug Ragnar Lagertha

Though it makes sense that Lagertha, the ex-wife to Ragnar, would harbor some bitterness with his current wife Aslaug, it would seem that more anger should have been diverted to the man himself. To top this off, Lagertha fatally ends this rivalry with a pretty questionable move, taking her out just as Aslaug accepts defeat and decides to step down as Queen of Kattegat.

One can perhaps justify the slight to Ragnar, but her move is also a slight against his sons, who had no role or control in this conflict. This instantly makes her a target for the ruthless, short-fused Ivar, who vows to avenge his mother and kill Lagertha.

Best: Ivar Vs Bjorn

Vikings reaches a thrilling climax at the end of season 5 and into season 6, which largely stands on the strength of this epic rivalry. Here you have 2 prominent sons of Ragnar and practiced fighters. They're born to different mothers and are vastly different outside of their strength and shrewd, tactical nature. You've got the more caring and honorable nature of Bjorn, versus the maniacal, ruthless killer that is Ivar the Boneless.

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Though things branch into complexity with various factions, the show builds up and conglomerates around these 2 major rivals, making for some exciting battles and memorable exchanges.

Makes No Sense: Floki Vs Athelstan

Floki murders Athelstan after getting a sign from the gods in Vikings

One of the biggest head-scratching moments for many viewers comes just before Ragnar's major campaign to conquer Paris, which sees his friend Athelstan slain by Floki. Of course, there was the staunch Paganism and Christian followings of these rivals which would naturally create some conflict. Still, it's tough to see the logic behind this ill-advised murder.

Not only were both of these men close to Ragnar, but Athelstan had long-since proven a useful, open-minded ally. Floki's hatred towards the monk doesn't quite seem justified or explained well enough - outside of some vague Pagan fanaticism or jealousy by the ship-builder.

Best: Ragnar Vs Rollo

2 of the most prominent figures in Vikings also happen to be its biggest rivals. In actuality, Ragnar and Rollo resided in slightly different time periods (and were not actually brothers) as per historians and show creator Michael Hirst. Regardless, both of their event-filled lives are blended into one epic tale here, making for a captivating rivalry full of drama.

Both men rise from the depths to glory in their own way, yet their paths in obtaining it a very different - and are often at odds with each other. You've got one of the most iconic Viking leaders, versus the Viking-turned Frankish count. These 2 memorable characters have a rich history as allies and foes, which ebbs and flows during the first 4 seasons. This builds up to an ultimate showdown as Ragnar's army clashes with the Rollo-led Franks.

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