Map showing the population density of the British Isles in 2011, within the constituent countries of the UK, Ireland and the crown dependencies.
Population data is from the 2011 censuses for the United Kingdom, Ireland, the Isle of Man and Jersey, and the 2011 population estimate for Guernsey. 
Background map:
Ordnance Survey OpenData Boundary-Line:

GB dataNational Geospatial-Intelligence Agency

Other data
Nilfanion, created using Ordnance Survey data