Vikings: Every Character Based On Real Historical Figures
1. King Horik
King Horik was in the first two seasons of Vikings where he got Ragnar to help him usurp the Danish king's power. However, when he in turn got worried about Ragnar's increasing power he tried to manipulate and betray him.
In reality he was a Danish king who ruled in the early-mid 9th century and he had a great hatred for the Franks and conversion to Christianity, so the show got those things right. However the real King Horik was killed by his own nephew as revenge for being exiled, rather than by Ragnar.