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The decision has been made: 17,410,742 people of the United Kingdom’s 65 million population voted for leaving the European Union. These are about 26.8% of the UK’s resident population, or 37.4% of the electorate in this EU referendum. It also equals 51.9% of the valid votes cast, as stated in the official figures from the electoral commission. 16,141,241 people (48.1%) voted for remaining a member of the EU, at a turnout of 72.2% of the electorate of 46,500,001. Apart from people not at voting age, EU residents living in the UK were not allowed to vote as other foreign nationals. Irish citizen living in the UK were given a vote in this referendum, as was the UK population in Gibraltar. The following map is a cartogram that shows 327 of the 328 electoral areas (Gibraltar is not shown in this map) from this referendum resized according to their total number of people entitled to vote. In addition, the vote share for leaving and remaining is shown in differently shaded densities. Unlike in the introductory map above (where blue stands for Leave and yellow for Remain), I now switch from the colours that have widely been used in the UK’s domestic media coverage (which even BBC’s David Dimbleby found hard to explain), to a colour scheme that I find more suitable, using blue (from the EU flag) for the remain votes and red (from the Union Jack flag) for the leave votes:

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Larger version with additional labels

A blog post on the Vis4 website explains why their (nice) mappings of the referendum was not made in cartogram form. I agree with some of the points they make, though I feel that cartograms can provide some useful additional perspectives on the outcome, which is why I have added my cartographic take on the referendum here. No single map can tell the full story of this decision that will have quite a lot of implications for the future of the United Kingdom, the European Union, and quite certainly also the whole world.
The next cartogram simplifies the above map by not including information about the vote share, but only showing which electoral area has voted for remaining in or leaving the European Union. The overall patterns show a very divided United Kingdom. The populations of Scotland and Northern Ireland have voted for remaining a member of the EU in all electoral areas, while Wales, and even more so England are split in their verdict of the quite close outcome:

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With 72.2% turnout among those that were allowed to vote (approximately 71.5% of the current resident population), participation in this referendum was higher than at last year’s general election (where 66.1% decided to vote), but lower than in Scotland’s independence referendum (where 84.6% of the residents in Scotland voted). The following cartogram shows the geographical variation in turnout:

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Cartograms can be used as a basemap for mapping elections and showing them from the perspective of those that matter, such as the electorate used in the above maps. But they can also be used for visualising the actual electoral data. As it was the case with mapping the Scottish referendum in 2014, showing the distribution of Leave and Remain votes very much reflects the distribution of overall votes or the electorate, as it is hard to distinguish the smaller differences between areas that such a close outcome produces. However, with a clearly split country, the dominance of Remain votes in Scotland and London becomes visible when comparing these two cartograms, as shown in the top row of the following map series where I used a consistent colour scheme to highlight the variation of votes between different regions of the United Kingdom (a land area map of the UK is included on the left for reference). The cartograms on the bottom include a cartogram of the electorate as it was used in the above cartograms, and then shows two maps where each electoral area is resized according to the the absolute surplus of votes for either Leave (middle) or Remain (right), so basically are cartograms of the difference in votes in each area for both sides of the referendum. Each electoral area therefore appears exclusively in only one of the two cartograms:

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While politicians on both sides of the argument (and outside the UK) scratch their heads about the implications of the referendum, many more maps could be drawn from the results dissecting the demographics that played an important role in the decision. For now, I leave it to these and recommend looking at the New York Times map by Gregor Aisch, Adam Pearce and Karl Russell if you want to see a more conventional perspective made in an impeccable cartographic manner.

The content on this page has been created by Benjamin Hennig using data by the UK Electoral Commission. Please contact me for further details on the terms of use.