I have several books by Jan Gillou: https://en.wikipedia.org/wiki/Jan_Guillou

Three of these are fictionalised accounts of the Knights Templar, g
together called The Crusades Trilogy: https://en.wikipedia.org/wiki/Crusades_trilogy.

There is also one book on witchcraft "Häxornas Försvarvare: en historiskt reportage" This is not in Wikipedia, but I found it in his own company -Piratförlaget: http://www.piratforlaget.se/bocker/h...skt-reportage/