Since we’re posting Venn diagrams… this one came to mind. I’m aware that it may spark controversy, but how else can you represent it so clearly?

From the author: “The Republic of Ireland and the United Kingdom are the only two sovereign states in this image. They are shown in red. Ireland and Great Britain are both islands and are shown in green. England, Scotland, Wales and Northern Ireland are constituent countries of the United Kingdom and are shown in orange.”

Oh… and technically it’s really an Euler diagram because it shows relationships other than pure intersections.