The Guardian just published a nice timeline-map visualisation on “how political shifts have altered the map of Europe” mainly showing the change of political left-right majorities across Europe over the past 40 years.
Let’s complement this with an academic perspective:
Through the analysis of 264 elections in 30 European countries (EU-27 + Norway, Iceland and Switzerland) in 8 five-year cycles between 1970 and 2008 (a similar time period as the Guardian chose), Daniele Caramani has found that party system patterns have become more and more similar across Europe over time.
This seems to be in particular true for those parties among the 25 party families identified that are situated on the classic left-right axis (communists, socialists, greens, liberals, conservatives, extreme right with the four party families on the middle-ground covering ~70% of the total vote share). In other words, voters across Europe have and seem to make similar choices on the left-right axis of the political spectrum.
The fact that there are still differences and heterogeneity in the electorates, so Caramani, can be explained by more culturally oriented parties such as “religious, agrarian and ethno-regionalist” parties for which voting patterns are more divergent.
The interesting thing is that looking at the voting timeline-map provided by the Guardian one could also suspect that beyond the more similar patterns of the party systems described by Caramani, voters appear to make the same political choices at the same time.
In how far this is actually true depends on the way we interpret the fact that party systems have changed over time (i.e. that a “blue” Italy 30 years ago may reflect a different party system than a “blue” Italy today) and how important the cultural dimension of the party systems plays into composition of what mostly are and were coalition governments.
Which doesn’t say the Guardian’s visualisation isn’t a nice and interesting visualisation.
The article “The Europeanization of electoral politics: An analysis of converging voting distributions in 30 European party systems, 1970 -2008” by Daniele Caramani was published online before print in March 2011 in Party Politics.