Belgium and the Netherlands are often taken and presented together as the 'Low Countries', and there are good reasons for treating the two countries as part of a single category. Both are textbook examples of divided societies which display the subcultural vertical segmentation that has travelled conceptually as verzuiling (or pillarization (Rokkan 1977)) and share the well-known features of consociational democracy. Being neighbours, moreover, Belgium and the Netherlands share much common history. Yet the border separating the two countries is highly significant, and explains a number of important differences between them.
The border goes back to the religious wars of the sixteenth century, and was formalized by the Treaty of Münster in Westphalia in 1648, thus creating a Dutch state with a very definite Protestant identity, although the political borderline ran south of the religious borderline, leaving a Catholic minority within the Netherlands. The southern provinces remained under various foreign rulers, until the Congress of Vienna reunited north and south as the Kingdom of the Netherlands in 1815. Fifteen years later the Catholic and Francophone elites of the south broke away and created an independent Belgian state. This new state was Catholic and officially French speaking, though the majority of the population did not in fact speak French. History matters greatly in understanding the subsequent development of democratic politics in both countries, and many relevant aspects of this history derive from the separations of 1648 and 1830 (Andeweg and Irwin 1993 : 7). In particular, it is impossible to describe the Low Countries without making reference to religion and language.
In both the Netherlands and Belgium, the major parties can be grouped into three party families: religious (Christian), liberal, and socialist. Religion is crucial for the Netherlands, where three religious minorities—Catholics, Protestants, and orthodox Protestants (Gereformeerden)—organized themselves and created