Last week a story surfaced that seemed, on the face of it, a little bit odd. A far right youtuber in Austria, Martin Sellner, had his house raided by the authorities after revealing he’d received a $1500 donation to his movement Generation Identity. The money was from the suspect in the Christchurch shooting in New Zealand. This story takes us from the world of YouTubers back to the Crusades and tells us how extreme ideas spread around the world.