Vikings 2.5 was a satisfying episode on the domestic front. As expected, Ragnar beat Jarl Borg. In the battle and aftermath, Rollo had a chance to demonstrate his life-and-death loyalty and value to his brother, and Bjorn got what we wanted - a continuing place with his father. Not expected was Ragnar first not killing Jarl, and then, based on the coming attractions, recruiting him for the return trip to Wessex in England.
And so the balance tips back to the conflict between Norse and English cultures, which is the part of the series I like best. We already know that Ecbert will be the most effective enemy Ragnar has ever encountered, if Ecbert stays an enemy. In episode 2.5, we learn that Ecbert spent time in the court of Charlemagne, one of Europe's all-time most effective kings and conquerors. Charlemagne was crowned Emperor by the Pope in 800, and was the first crown to rule over most of Europe since the collapse of the Western Roman Empire. Ecbert, in other words, had one good teacher by example in Charlemagne.
My guess is the fictitious Athelstan will play a crucial role in the battle or whatever the evolving relationship between Ecbert and Ragnar. Both men know this. One reason that Ragnar did not want to leave Athelstan in England - in addition to wanting his counsel and his knowledge by his side - was that Ragnar did not want to see Athelstan either killed or brought under Ecbert's influence. Ecbert understands Athelstan's value, which is why he saved him from the crucifixion.
And what does Athlestan think? He's now a classic Greek or Shakespearean tragic hero, a man caught in the middle of two cultures, almost perfectly and therefore intractably. He still keenly feels his religious roots, which are English, even as he feels a deep loyalty to Ragnar. In a significant exchange in episode 2.5, he says that ways of the Norse are in some ways better than what the English do, but not in all ways. It will interesting and memorable indeed to see where this former denizen of Lindisfarne comes down in the contest of cultures, which may or may not be to the death.