A number of different factors helped The Last Kingdom become one of Netflix's most surprising hit shows. Following Bernard Cornwell's Saxon Stories novel series, The Last Kingdom tells the story of the formation of England as a unified kingdom. The story is told through the eyes of its main protagonist, Uhtred of Bebbanburg, who is Saxon by birth, but was raised by Danes, making him the perfect medium through which to explore the Saxon-Dane conflict.
https://screenrant.com/last-kingdom-netflix-hit-reasons-why/