This research briefing explores if and how far-right narratives from the United States (US), France and Germany gain traction in domestic mainstream media, or move across borders between the US on the one hand, and France and Germany on the other. It tests what will be referred to as the mainstreaming hypothesis (far-right ideas start out in far-right alternative media but eventually move to the mainstream) and the transnationalisation hypothesis (far-right ideas spread between national media ecosystems).