en.wikipedia.org/wiki/Harald_Fairhair

The sentence is contradicted by the source it is summarizing.

In the Orkneyinga Saga tradition, Ivar is the son who dies during the expedition. The islands are then granted to Rögnvald as compensation for that loss. A modern summary quoting the saga states:

"In this expedition, Ivar, a son of Rögnvald, Earl of Moeri, was killed. In order to recompense Rögnvald for the loss of his son, King Harald bestowed on him the territory of the subjugated isles of Orkney and Shetland..."

So the article's wording is wrong because its pronoun makes it say Harald gave the islands to Ivar, who had just been killed, rather than to Rögnvald.

This is also consistent with the next sentence in the article itself, which says Rögnvald later passed the jarlship to his brother Sigurd—something that only makes sense if Rögnvald first received it.

Chapter 18 of Ragnars saga loðbrókar does not give the genealogy described here.

The chapter says, in Old Norse, that from Sigurd Snake-in-the-Eye a great lineage descended, and that his daughter was Ragnhildr, mother of Harald Fairhair. In other words, the passage connects Harald to Sigurd Snake-in-the-Eye via Ragnhild, not to Sigurd Hart via Aslaug → Sigurd Snake-in-the-Eye → Ragnhild.

So the article's sentence attributes the wrong ancestor to chapter 18 and reverses the genealogical chain. It appears to mix up different saga traditions about Harald’s maternal ancestry.

This sentence conflates the release year of the base game with the release year of the expansion.

Steam's official store page for Mount & Blade: Warband - Viking Conquest Reforged Edition identifies it as downloadable content for Mount & Blade: Warband and gives its release date as December 11, 2014. So describing it as a 2010 expansion pack is incorrect.

A correct phrasing would date Viking Conquest to 2014, while noting that the base game Mount & Blade: Warband was released in 2010.